So, you want to buy a flashlight? In the world of flashlights
there are 2 ways to go. First is to walk into a department
store and grab the first thing you find on the shelf,
trusting the marketers who made the packaging flashy
and appealing to the eye. This is generally considered
a big mistake for any consumer product! Usually flashlights
bought in this way wind up in a kitchen drawer as "dead
battery holders". The other is to really think
about your purchase, do some research, and buy a good
light that suits the needs that you have. This is by
far the best way to avoid disappointment and to find
a personal lighting instrument that you can rely on
and depend upon for many, many, years.
In this article I hope to help the general consumer
gain a little knowledge about what they may be getting
into, some of the pitfalls, and the myriad of different
options currently available on the market. You may be
stunned to find out about the number of various styles,
designs, and capabilities of the latest generation of
personal lighting devices available.
The first thing you have to think about is "What
am I going to use this for?" I don't mean just
for 'seeing in the dark'! Are you going to use this
on the job, in an industrial setting, camping, diving,
search and rescue, caving (spelunking), general household
use, etc. Based on what the flashlight will be used
for you can decide what features will be needed and
which would just be additional cost or bulk. For example,
if you were going to use a light for general household
tasks, it may be advantageous to get an alkaline battery
powered incandescent that runs on D cells since size
and weight are not going to be a big factor if it just
sits in a corner until it is needed. If you are going
backpacking, you will probably want a small, lightweight
flashlight that uses LEDs for efficiency so you don't
need to carry lots of additional spare batteries in
your pack. As I go through the various features available
in lights these days I'll try to point out the benefits
of each so you can make a more informed decision about
Hand held flashlights are great for brief tasks, but
if you are in an extended power outage, or setting up
camp, nothing in the world beats a headlamp for hands
free lighting. If you can get over the fact that you'll
look like a miner or a geek, you won't regret it. Trying
to set up camp with one hand is just about impossible.
So are most daily tasks in the dark. I always thought
headlamps were goofy until we had the power out for
an extended period. Now I make sure I have one ready
and fully loaded with batteries for each family member.
Materials / Finishes
The material that the body of a flashlight comes in
is sometimes an important consideration. Generally you
will find 2 types of body materials: Aluminum and Plastic/Polymer.
Aluminum bodies are found on a variety of "better"
lights, the most common example of which is the Mag
series of lights. The aluminum bodies are fairly durable
and although subject to deformation from sharp impacts,
they can usually take a beating. Most aluminum lights
come in a standard flashlight cylindrical shape since
the shape is the easiest to make when machining aluminum.
When looking at an aluminum light consider the finish.
There are 3 primary types of finish on the market today.
'Powder coated' is considered the weakest finish. This
type of coating is paint that is bonded to the metal
with heat. It will protect the metal from corrosion,
but it can also scrape off. The next strongest finish
is anodize type 2. This is what you will find on a common
light. The finish is actually the result of an electro-chemical
process that forms a layer of oxidization on the surface
of the metal, which is then chemically colored. The
process can produce a wide variety of metallic finish
colors. Anodize will wear off and ding, but it holds
up pretty well to general and some rough use. Anodize
type 3 is the hardest finish available for aluminum.
Like anodize type 2 it is actually the result of an
electrochemical process but is very, very hard. Type
3 will take a very serious beating and will often wear
away other metals before it takes damage. Powder coating
and anodize type 2 finishes are good for most folks
and tasks. If your light will be subject to a lot of
bangs/dings/friction, consider a type 3 anodize finish.
and all Arc
brand flashlights use type 3 anodize.
Plastic / Polymer
Lights made with plastic or polymer tend to come in
a greater variety of shapes since the plastic can be
molded rather easily into nearly any shape desired.
You'll find flat ones, round ones, and nearly everything
in between. Plastic and polymers come in a large variety
of grades and types - far too many to mention here.
Generally the more expensive lights are made of better
quality grades of polymers that can take a beating.
There are a number of advantages of getting polymer
lights. Polymer lights are the same color all the way
through the body, so nicks and scrapes don't show up
as readily as on aluminum lights. Polymer lights are
naturally resilient and tend to flex instead of bend
or dent when subject to impact or drops. They can be
found in both very dull colors and very bright fluorescent
colors, so if either discretion or visibility is your
concern, you can find a light that suits your purpose.
For many purposes it may be wise to get a light that
is brightly colored and easy to identify so that if
it is placed down somewhere it is easy to spot against
the background. This is especially important when hiking
/ backpacking / camping.
There are several types of bulbs that are available
for flashlights. Bulbs can be broken down into three
main categories: Incandescent, LED, and fluorescent.
Incandescent bulbs produce light by heating a tiny,
fragile filament almost to its melting point. The filament
glows brightly in protest, producing usable light. As
the batteries lose power, the filament cools and produces
light that is more and more yellow until it finally
LEDs produce light by taking the energy of the batteries
and turning most of it directly to light. LEDs tend
to be very efficient at lower light levels and do not
turn yellow as the batteries are depleted. Instead they
just produce less light, but of the same color.
Fluorescent bulbs light an area by causing a filament
inside to emit energy that causes a surrounding layer
of phosphorescent material to glow. The light from these
bulbs is a soft area light and cannot be focused into
Let's take a quick look at the construction of incandescent
bulbs out there and the merits of each.
"PR based" bulbs are the common flashlight
bulbs you find. They have a metal base with a contact
at the bottom, a metal collar at the top of the base
where the glass envelope is attached, and a filament
in a glass capsule. These bulbs are usually held in
place by the metal collar and do not move if dropped
or impacted. However, drops and impacts will sometimes
cause the hot filament to flex and break.
Bi-Pin bulbs are simply a glass capsule with the filament
inside and two pins coming out of the base of the glass
bulb. These bulbs are pressed into a socket and rely
on the socket to hold them in place. If the socket does
not hold the pins tightly the bulb may pop out of its
socket if the light is dropped on its face, leaving
the bulb rattling around inside the reflector. Repeated
bangs can loosen the bulb and cause the focus of the
flashlight to change as well. Usually opening the light
and a gentle press with the fingertip will push the
bulb back into place if it moves. Because they lack
the metal base they are usually rather small in size
and therefore it is very easy to carry spares or to
fit a spare right in the flashlight itself. These bulbs
are found in the Mini
Maglight and the Streamlight
Lamp assemblies are usually the most secure of the
bulbs. Generally these consist of one of the two types
of bulbs listed above that are permanently mounted in
an assembly or carrier that is installed into the light.
Some lamp assemblies only have a carrier for the bulb
and some have the reflector attached. These tend to
be more expensive than the above two. Surefire
lights use complete lamp assemblies.
Regardless of the type of bulb assembly, note that
all incandescent filaments can be subject to breakage
if dropped or subjected to impact. It is the nature
of the beast. White hot tungsten does not react well
to being banged around.
All of the above bulbs come in a variety of chemistries.
"Standard" bulbs are bulbs that have nothing
but a vacuum inside the glass capsule around the filament.
These are the most inexpensive and produce the least
light of the bulbs available.
Krypton bulbs are by far the most common. These tend
to be the "regular" flashlight bulb that you
get with most inexpensive lights. The glass envelope
surrounding the filament is filled with krypton gas,
which helps the filament produce more light.
Halogen bulbs are brighter than the above two and tend
to draw more electricity. They also seem a bit more
durable. The glass envelope is filled with a mixture
of halogen gasses, which help preserve the life of the
filament and make it brighter.
Xenon bulbs have the glass envelope filled with xenon
gas. Like the halogen and krypton bulbs, this helps
lengthen the lifespan of the filament and produce more
light. In the case of xenon bulbs, however, the light
produced is a very pure white light - much more so than
any of those above. Xenon filled bulbs are about the
best you can get for common incandescent flashlights.
HID bulbs, or High Intensity Discharge bulbs are a
little different from incandescent filament bulbs. They
produce light my making a tiny spark between a gap in
a pair of electodes to heat a gas in the bulb to a temperature
where it incandesces (emits light). These are found
in some high end dive lights and some military lights.
These are extremely bright. This is the type of bulb
found in those "bluish white" car headlights.
(By the way, if the headlights on a car give off really
blue or bluish green light, those are just regular bulbs
coated with a tint in a pathetic attempt to look like
the expensive HID headlights.)
LEDs are fairly new on the scene of flashlights and
they are really taking off. They tend to be much more
energy efficient than incandescent bulbs, running 5-10
times as long on a set of batteries, and they won't
"blow" if subjected to impacts. They have
very long lifespans, lasting into the thousands of hours
in normal use, unlike incandescent bulbs, which generally
tend to fail after 5-20 hours of use. However, they
are not as bright as incandescent bulbs, but that is
LEDs are available in a variety of different colors
- nearly every color of the spectrum. Let's take a quick
look at some of the various colors and what they are
White: General all around best
color for our vision. Give excellent color recognition.
All the rest can be considered "special purpose"
lights and do not allow color recognition at all. Essentially
using any of the colors below is the same as seeing
things in "black and white".
Red: Night vision preservation at low
lighting levels. More info here.
Amber: Focuses well in the eye
and is usually a very "comfortable" monochromatic
light to use
Green: Doesn't cause military night vision
equipment to overload or "bloom" when used.
Does NOT preserve normal human night vision despite
Blue: Good for hunters following the
blood trail of wounded game. The blood shows up as solid
black in this light.
Cyan: Brightest of the monochromatic
colors. Some people just like the look of it.
There are 3 primary types of LEDs you'll find in flashlights.
3mm LEDs are tiny LEDs that are used in some very
small lights. Due to their size they produce the least
light of the LEDs.
5mm LEDs are the most common LEDs to find. They have
been used in specialty lights for some time and are
now working their way into flashlights that can be
bought at common department stores.
High Power LEDs are very large LEDs that run hot.
These LEDs produce light that is starting to rival
incandescent bulbs. Surefire
Flashlight use these LEDs in some of their lights.
These LEDs includ the Luxeon brand as well as many
others. Luxeon have historically been the most popular
and they come in a variety of types and Wattage consumption.
Luxeon I (Luxeon Star, 1 Watt) Low Dome LEDs: These
are fairly bright, but there has historically been
a lot of variation in the tint of the LEDs. Some
appear greenish, some bluish, some purpleish. Beam
pattern is generally a hollow cone of light. Special
optics and reflectors correct this to produce a
nice spot of light.
Luxeon I (Luxeon Star, 1 Watt) High Dome LEDs:
Output similar to the Low Dome LEDs but light pattern
is much more even. These can be focused into a tighter
beam in general than the Low Dome Luxeon due to
the shape of the epoxy capsule around the LED.
Luxeon III LEDs (3 Watt): Always "high dome".
These are really very robust Luxeon I LEDs which
can handle much more current and can produce more
Luxeon V LEDs (5 Watt) are very bright but require
considerably more power than the Luxeon I and III
LEDs. These tend to run very hot and need additional
heatsinking to protect the LED from thermal breakdown.
Output rivals and surpasses that of many common
incandescent flashlight bulbs, but the size of the
emitter often results in a slight hollow spot in
the middle of the beam.
Luxeon K2 LEDs (7 Watt) are the next generation
of Luxeons and designed to run at around 6-7 Watts.
As of September 2006, these are just starting to
appear on the market.
At the end of 2006 / beginning of 2007 two new High
Power LEDs have appeared on the market. The Cree XR-E
and Seoul P4 are both about "3 Watt" rated,
but are about double the efficiency of Luxeon "3
Watt" LEDs. (By the way, wattage is a measure
of power consumption, not light emission).
This means that you can have either the same brightness
as the Luxeon with about double the runtime, or about
double the brightness with the about same runtime.
I'm sure the technological advances in the industry
will continue this trend of increasing efficiency
Single 5mm LED lights tend to produce plenty of light
for close tasks in complete darkness and last a very
long time on a set of batteries. The CMG
Infinity and the Arc
AAA are examples of this application. Multi 5mm
LED lights produce a wide flood of light and also tend
to last a long time between battery changes. This type
of light would include the Tektite
Expedition with 7 LEDs, the
Lightwave 3000 and 4000
with 7 and 10 LEDs respectively, and the Streamlight
4AA LED with 7 LEDs.
If you are looking for a light that will produce modest
amounts of light for very long periods of time, consider
5mm LED lights. LED lights with a number of 5mm LEDs
will produce a very good amount of light for a very
long time. Remember too, that dropping an LED light
will not blow the bulb, so they tend to be very reliable
sources of light. The primary disadvantage of 3mm and
5mm LED lights is that the light cannot be easily focused
into a tight spot and therefore generally cannot light
up a subject at any distance from the observer.
Luxeon LED lights can be focused very well using special
manufactured optics or reflectors which causes the light
to rival common incandescent lights, and yet retain
some of the advantages (long life, doesn't blow) of
the LED lights. However, since they put out much more
light than their 5mm LED counterparts, do not expect
the super long battery life that the former can achieve.
All things being the same, brightness and battery life
are in inverse proportion to one another. You have to
give up one for the other. The Elektrolumens
Blaster 3P is a great example of a Luxeon I LED
light that is very bright and the Surefire
L4 is an extremely bright Luxeon V light.
There are some new high powered LEDs out
on the market now, including the Nichia Jupiter and
the Nichia Rigel.
Various overseas companies are also making
some other "High Power" LEDs as well. Be warned,
some of these "high powered" LED bulbs are
not the same quality nor as effective at producing light
as the name brand LED bulbs. Be cautious of very low
priced LED lights. Remember, you get what you pay for.
In year end 2006/early 2007, both Cree
and Seoul Semiconductor came out with new 3 Watt rated
LEDs (XR-E and P4, respectively) which just about double
the efficiency of high output LEDs. This means that
they can either run about twice as long as the then
current Luxeon brand 3 Watt LEDs using the same power
source, or run about twice as bright with the same runtime.
These new LEDs can run brighter and longer in 6V applications
than "high powered" 6V incandescents like
the Surefire P60 lamp flashlights (G2, C2, M2, 6P, G2Z).
These new LEDs essentially both catch up with and surpass
tradidional incandescent bulbs used at these voltage
levels. See the Huntlight
Neo T5 and Fenix
P3D-CE for examples. This marks a major turning
point in LED technology.
Fluorescent bulbs are used for area lighting.
There are two types currently on the market: Compact
Fluorescent Tubes and Cold Cathode Fluorescent Tubes
(CCFT). Compact Fluorescent Tubes are not as efficient
as CCFT, but both produce nice even lighting for an
area. Light from these tubes really cannot be directed
very well and are not sufficient for lighting anything
but the immediate area around the flashlight.
Batteries can be broken down into 3 basic types: Rechargeable,
Alkaline, and Lithium. The size (capacity) and type
of battery you choose will be directly related to how
you use the light. Let's first take a look at the different
battery sizes available.
AAAA: Very thin cylindrical cell. Not
much power capacity, but allows for very thin flashlights.
Used in some lasers and the Streamlight
Stylus LED pocket light.
AAA: Small cylindrical cells. Decent
power capacity for less powerful lights. Good for headlamps
where the batteries sit on the front of the head, such
as the Eveready LED or the Streamlight Trident. Also
good for small keychain or pocket lights such as the
AAA or the Princeton
Tec Attitude or Impact
AA: Cylindrical cells. Good power capacity.
The most common battery you can find. This is probably
the best mix of size, power capacity, and price you'll
find for small flashlights, both LED and incandescent.
C: Larger capacity cylindrical cells.
Lights based on these cells tend to fit well in the
hand of most users. Same height as AA cells, but larger
D: Largest of the common batteries with
the highest capacity. Also the heaviest. These tend
to be used in bigger lights or where runtime is a major
9 Volt: Square cells with the same capacity
as AAAA batteries, but at a higher voltage. Used for
low-drain applications including the Palight
single LED light.
Lithium 123: High output "camera"
batteries that produce 3 volts each. Very lightweight
and produce very high currents. Used in lights that
draw lots of current, such as Surefire.
Before using lights that utilize this battery type,
you may want to be aware of some precautions since they
can burst violently if used
Lithium AA: Can be used in place of Alkaline
AA in many cases, but not all. Very lightweight and
also can produce high current if necessary. Great for
backpacking applications due to their weight.
Lithium Coin Cells: Flat cells about
the size of a nickel or quarter that are commonly used
in keychain LED lights such as Inova
Microlight or Photon
2. Not much capacity at all, but very small.
More info here.
Rechargeable: Come in a large variety of sizes and
are usually built in to rechargeable flashlights. Rechargeable
lights are best used in applications where the light
will be used frequently for relatively short periods
with time to recharge between uses. Great for a general
household light since they can be left in the charger
and you know it will always be ready for use.
Rechargeable Nickle-Metal-Hydride (NiMH) cells can
usually be used in place of alkaline batteries, but
sometimes with reduced runtimes and brightness. (Flashlights
designed for recharging that include the rechargeable
batteries built in will have bulbs matched to the voltage
of the rechargeable cells inside.) If left in the flashlight
unused, rechargeable cells tend to lose their charge
rapidly over time (dead in 1-2 months). This is known
as "self discharge" and is a common problem
with NiMH, and other, rechargeable cells. As of 2006,
several companies including Titanium (Power Enduro),
Sanyo (Eneloop), and Rayovac (Hybrid) have developed
"low self discharge" NiMH rechargeables which
hold about 80% of their charge for over a year without
charging if left unused and are fully charged right
out of the package.
Lithium Ion rechargeable cells are coming on strong
in the marketplace right now (2006). Flashlights purchased
with Li-Ion rechargeable cells are designed for their
use and they can provide very high outputs at very low
long-term operating costs, but lights using these cells
tend to be more expensive. As a result there is often
a tempation to retrofit a current light to use these
cells. If you decide to retrofit a current flashlight
with Li-Ion rechargeable cells, you should make yourself
aware of some dangers in
Alkaline: The most common battery formulation to date.
Alkaline batteries work best in lights that draw low
to moderate current, which includes most common lights.
They have a shelf life of up to 7 years. During use
they will deplete, rapidly at first, reducing the light
output from a flashlight over time. They are available
almost anywhere. They do not hold up well in cold weather.
Lithium: Made of a lithium metal formulation, these
batteries tend to be able to produce higher currents
than alkaline batteries and are not affected by cold
weather as much as alkaline batteries. Because they
use lithium metal, they are very lightweight, to the
point where some waterproof lights float with lithium
batteries inside. The only "common" sized
battery you will find with a lithium formulation is
the AA made by Energizer. 123a lithium batteries commonly
are used in high output, short run incandescent lights.
Lithium batteries are more expensive than alkaline batteries.
In common usage, the piece of glass or plastic in front
of the reflector is called a "lens". It's
purpose is usually only to protect the bulb and reflector
from the environment rather than actually changing the
shape of the light from the bulb. It is therefore better
called a "window" than a "lens"
since light passes though it unaffectted. A true "lens"
shapes the light and some lights do use a true lens
to change the shape of the beam. Some lenses are very
complex, such as the Inova TIR (Total Inernal Reflection)
lens which captures almost all the light from the bulb
and shapes it in a very specific way. Throughout this
site, we use the common usage definition of the word
"lens" when talking about flashlights.
Lenses come in a variety of materials. Most of the
time the lens at the end of a flashlight is plastic.
Some flashlights use Lexan - a clear plastic that will
not shatter and is temperature resistant. Others use
glass of various sorts, including Pyrex. Glass lenses
are usually found in high output flashlights that produce
a lot of heat. Plastic lenses would be subject to melting
under those conditions.
Tec Impact uses a single LED behind a focusing lens
that allows the LED to produce a spot of light. Although
not very bright, it does allow the LED to be used at
a moderate distance, unlike most other single LED lights.
The purpose of the reflector is to gather light that
would otherwise be projected to the sides and instead
project it forward, out through the lens. Reflectors
may be plastic or metal, depending upon the heat resistance
needed inside the head of the light. Basically, there
are two types of reflectors: Smooth and Textured.
Smooth reflectors have a shiny smooth surface that
surrounds the bulb. This allows for a very bright spot
of light to be sent from the light. Smooth reflectors
produce the tightest and farthest-reaching beams. This
works well if the bulb is properly placed in the reflector.
However it the bulb is too far forward or too far back,
rings of light and dark spots appear in the beam pattern.
Textured reflectors use facets or a rough appearance
to smooth out the rings and dark spots produced by smooth
reflectors. The light will not produce as tight of a
beam as one with a smooth reflector, but the light is
well distributed. Many "better quality" lights
use reflectors that are textured. If the quality of
the beam is important it may be worthwhile to investigate
textured reflectors. More info here.
The seals in a light are going to keep the environment
out, allowing for greater reliability of the light.
Depending on the tightness of the fit of the seal, a
light may be water resistant, waterproof, or dive capable.
For use on a boat, it may be a good idea to look for
a floating light in case it gets dropped overboard.
Seals are usually found between the lens and the head
of the light, between the head and the body of the light,
and between the tailcap and the body. Most commonly
the seals in a light are o-rings or gaskets.
O-ring seals are simple rings of rubbery material that
sit in a groove at the head or tail of the light and
create a tight seal when the head/tail is attached.
O-rings are commonly found on cylindrical lights and
depending upon the size and tightness they can allow
a light to withstand significant water pressure. The
Tec Tec40 is a dive capable o-ring sealed light.
Gaskets are usually found on irregular shaped lights
or lights with irregular shaped openings. The gasket
is pinched between 2 parts of the light and held in
place by the fasteners between the two parts. The Eternalight
Ergomarine uses a gasket between its two halves.
Gaskets can work just as well, and sometimes better
Both gaskets and o-rings should
be kept lubricated. Rub them with a light coating
of silicone grease. Although lots of "specialty"
O-ring lubricants are available, a tube of common dielectric
silicone grease from an automotive store is inexpensive
and works as well as anything. Don't use petroleum based
products on the seals, as some seals are damaged by
There are so many different switches I'll only mention
a few of the common ones here. The type of switch is
again dictated by how you want to use the light.
Bezel twist: Very common type of switch. Twist the
bezel for on/off. This type of light usually requires
two hands, but many are more water resistant than others
since the bezel is the only opening in the light. The
bezel is usually removed for battery changes. Example:
Princeton Tec Tec40
Side click switch: Also very common, found in some
lights. Allows for one handed use. Can be made water
resistant with rubber seals.
Tailcap Click: Similar to the side click switch. Usually
operated with the thumb. Example: Streamlight
Tailcap twist: A bit less common - twist the tailcap
for on/off. May be combined with a momentary tailcap
press switch. Example: Surefire
Membrane press: A plastic membrane covers the switch.
Press the membrane to activate the switch. This allows
the switch to reside under the surface of the light's
body. Example: Eternalight.
Magnetic Reed: The magnetic reed switch has 2 parts.
A magnet attached to a sliding switch outside of the
light and a glass encapsulated reed on the inside. As
you slide the switch the magnet moves into a position
where it attracts the little reed and closes a circuit.
This type of switch allows the light to be completely
sealed - no opening is needed. Example: Nightstar
Side slide switch: Common in less expensive lights.
Very hard to waterproof. Example: Eveready
Circuitry? In a flashlight? Yup, you bet. Some flashlights
have circuitry to allow them to do a variety of functions
while others have step-up or regulator circuits. It
all depends on what you need! Usually you'll find special
circuitry only in some LED lights, but a few incandescent
lights use circuits as well.
Function circuitry: This circuitry allows the light
to perform a variety of different functions such as
dimming and blinking. The Princeton
Tec Eclipse is a keychain LED light that you press
the on off switch once for bright, twice for medium,
three times for dim, four times for slow blink and 5
times of fast blink.
Step-up circuits: These circuits boost the voltage
from a battery or batteries to run a bulb at a brighter
than expected level. 5mm LEDs require 3.6 volts or more
to operate properly. The step-up circuit in the Arc
AAA and Infinity
Ultra allow the single LED lights to work on only
one 1.5 volt battery by boosting the voltage.
Regulator circuits: These are the most desirable of
circuits. These circuits regulate the voltage going
to the bulb so that light output is constant throughout
the battery life - a flashlight that doesn't dim until
the very end of the battery life. The Opalec
Newbeam 3 LED light uses just such a regulator.
A2 is one of the few lights that uses a regulator
for an incandescent bulb.
Damn Lies, and Marketing
The last thing I would like to leave you
with is this: Let the Buyer Beware! When you read the
package about a product, remember that the material
you are reading was put there by marketers who have
only one purpose in mind: to separate you from your
money before someone else does.
If the light claims to last thousands
of hours between battery changes, can take a 44 caliber
bullet without breaking, or will still work if submerged
to depths that will crush a whale, don't believe it.
Instead visit our Reviews
pages and read what we think of the lights. Also
visit the pages of our esteemed reviewer colleagues
such as Craig at the LED
Museum or Chris at TorchReviews,
or come visit all of us at Candlepower
Forums where we have a specific forum dedicated
for members to post reviews of their own. We all do
our best to give honest reviews and help you, the buyer,
make good decisions about lights you may want or need.