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Tactical Flashlight Crash Course

A crash course on tactical flashlights

In order to choose the best tactical flashlights for your needs, you need to know the basics.


  • Purchase only from companies which are top quality legitimate manufacturers are listed in this guide. (You can check my post reviewing all these companies here.)
  • The Internet is full of cheap knockoff tactical lights – “2 for $12.99” etc., should be a clue – stay away from them. If you can’t Google the brand name of the flashlight, and find a legitimate manufacturer to back it up – don’t buy it!


  • Almost all of the top companies offer limited lifetime warranties. This doesn’t cover batteries and abuse but if a button goes bad, or it just doesn’t work – you’re covered.
  • Klarus, Olite and Nitecore offer 5 year warranties. Essentially, all parts, again except batteries, are covered.
  • Pelican offers a limitless lifetime warranty. If anything goes bad, again, except batteries, you’re covered.
  • Keep your receipt – warranties usually  only apply to the original purchaser.


  • Alkaline batteries include AA and AAA.
    • AAA batteries are available in alkaline and lithium and are normally used in pen lights.
    • Probably the most common alkaline battery is the AA. The 14500 batteries, is the rechargeable lithium equivalent of an AA batteries. 14500s are more powerful, but should only be used if the manufacturer specifies they are compatible with your flashlight.
      • In a few lights, AA batteries can be used as alternatives to 123A and even 18650.
  • Lithium 123A batteries.
    • CR123A are not rechargeable, have a lower voltage then rechargeable 123A batteries, but have a longer shelf life – usually 10 years.
    • Rechargeable 123As are known as RCR123A or 16340s; they have a higher voltage than the CR but  a shorter shelf life.
    • Recommendations
      • 123A are probably the most common batteries for tactical lights.
      • Ensure your light can use the RCR123A  before using.
      • For SHTF and bugging out etc., the CR123A are a good choice because of its long shelf life.
      • Otherwise, both types are great choices.
  • 18650 batteries.
    • Many lights are configured for 2 123As or 1 18650.
    • 123A are lighter but have less power and run time than an 18650.
    • Newer 20700 and 21700 lithium are the same size as the 18650 but have higher capacity and volume. Again, ensure your light is compatible before using.
    • With the current interest in vaping and their use of 18650 batteries, these batteries will continue to get better and better.
  • Internal Lithium packs.
    • Some lights have an internal lithium pack that is specific to a light and is rechargeable via magnetic or USB connection.
    • These power packs are more common in high powered search lights and some keychain lights.
  • Lithium Batteries
  • Chargers
  • Screen Shot    at
    • There are a number of available chargers for these batteries. One recent addition, that should be owned by anyone who travels is the Nitecore LC10, which won the 2019 ISPO award for technology.

Features & Applications

  • Common features include different light levels and strobes and even different program modes. These modes will retain a sub-set of the lighting configurations which are most useful for tactical use or camping use, etc. You also have power levels indicators as well as the ability to lock out the light to prevent accidental discharge. Many also include electronics to avoid reverse polarity issues. A few even have stepless and automatic light adjustments automatically based upon the environment.
  • Common applications include pen lights to every day carry.
  • Special applications may include law enforcement use of one light level and momentary on off only, to mitigate any lighting error, to intellibeam to avoid splash back, to intrinsically safe for explosives and flammables, to UV for anti-counterfeit authentication (bank cards, id and currency) to search lights to hunting applications. They’re all here in the above post and on this site.


  • Most of the best lights are constructed with aircraft aluminum. Some models (Streamlight and Pelican for example)  are starting to use polymer which is lighter and more comfortable in cold weather (since they don’t get as cold as aluminum.)
  • The lens of quality lights, will be some sort of anti-reflective treated crystal vs. the plastic or cheap glass used in poorly made products.
  • CREE LED bulbs are the best lights available and come in numerous configurations to optimize the brightness and run time designed by the manufacturer. All of the lights in the Definitive Guide use only CREE LEDs.
  • The reflector cone, which houses the CREE LED light is specifically designed to optimize (focus or spread) the light. Some manufacturers, like Surefire, custom make these cones, which add to the cost and desirability of the light.
  • Water resistance rating – Although lumens are not regulated, water resistance is tested by a scientific panel and ratings are assigned to flashlights.
    • Here’s the complete listing of IPX water resistance ratings.
    • Recommendations – If you’re going to be around water make sure your light has a IPX rating of 7 or 8. Most of the lights in this guide are rated at least a 7. Unless you’re scuba diving, you’re going to be fine.
  • Buttons and switches
    • Although some lights are twisted to turn on, off and access different settings, most lights have either a side or tail switch or button and some have both.
    • The easiest control point is the tail switch or button, because the grip is more like an ice pick vs. a sword grip. Lights with both a side and tail button are also good choices.
    • Check out the InfoGraphic on the Construction of the Best Tactical Lights here.


  • Weight –
    • Weight is in ounces. Some companies list weights with batteries, while others list weight without batteries. Still others don’t say if the battery weight is included or not. Keep this in mind when you review the various offerings.
    • Additionally, lights with optional battery configurations will weigh differently. For example two 123As will weight less than one 18650 battery (approximately 34 grams vs. 43-45 grams.)
  • Length –
    • This is self explanatory and is simply the length in inches from end to end.
    • Length is important because of intended use. For example, 4 or 5 inches is more appropriate for every day carry than a 9 inch light with more lumens.
  • Lumens –
    • Simply stated, lumens equal brightness. A 100 watt incandescent light bulb is approximately equivalent to 1600 lumens.
    • All flashlights from the top quality manufacturers utilize CREE LED bulbs. You will never change a flash bulb. For example if you run the light 6 hours a day for 365 days a year, it could last for 23 years.
    • LED’s are low energy and high efficiency bulbs and are almost indestructible.
    • There are no government regulations to ensure lumens are stated correctly. The manufacturers listed in this guide, however, have been shown to list their lumens truthfully. That is not the case with the cheaper light companies where lights listed as 1200 lumens are tested to be closer to 300 lumens.
      • You may notice some manufacturers state their lumens as 1000 or 1200 while other may state 844 or 926. These numbers are probably more accurate but as of yet, we have no lumens police to enforce accuracy and again, you need to rely on the manufacturer vs. the advertising.


  • Want a smaller pen light? Sort on battery and look at the AAA lights. These are usually the smallest and will effectively be the size and shape of a pen. Some are UV if you’re looking for document authentication.
  • Looking for every day carry (EDC)? Search on CR123A. Most EDC are about the size of one CR123A. Look at the images and check out the Amazon reviews. Also look at the prices relative to the costs and amount of Lumens. All are great lights but only you know your needs.
    • Some come with USB chargers which can either charge the battery directly or are inserted into the flashlight itself to charge.
    • Tactical Lights usually come with a non-roll construction and some type of striker concept on the front of the light. They will be be water resistent (remember check if their IPX rating is 7 – a very few will be 8.) See if the size and price are good for you and check them out.
    • You can find aluminum and polymer lights. Polymer are lighter and don’t get as cold in the winter. Both are solid choices.
  • Want a bright light for the bedside? You’re probably looking at 2 123As or 1 18650. These are bright but make sure that you have access to strobe easily and that the light has a tail button. These are pretty common. Again, check the sizes and prices to see if you can find a match.
  • Want a specialized light?
    • UV lights are available for authentication purposes – credit cards, ID’s and money.
    • Work in an environment where unintentional sparks could cause a disaster? Look at a Intrinsically Safe light.
    • Search Lights? These lights not only have higher lumens but more distance. Many come with a internal battery pack. Search search lights and review the costs vs. lumens and size.
    • Need a rail light? Simply sort on rail and check out the sizes, lumens and prices. Some have internal battery packs also.
    • Need a hunting light? Search on hunt and check out the available lights. Again, look at size, cost and lumens, then check out the various features such as light colors, etc.
  • The growth in technology makes the best tactical lights even better year after year. As in all technology, we are getting to the top of the growth curve such that changes are now occurring in smaller increments. Now is the time to buy.