Flashlight Fundamentals for Security and Investigations

A flashlight is an essential tool for anyone who works as a private investigator, security guard, process server, loss prevention officer, repo agent, or fugitive recovery.

If you know me, you know that after years of online teaching and preaching, I’m not a fan of “stuff”. I usually refer to these objects as toys.

I believe you carry your almost everything you need in your head. But, yes, you will require some tools and one of the few you need is a flashlight.

1. Power / Brightness

How powerful does the flashlight have to be? How bright does it have to be?

This is measured in lumens.

Don’t be distracted by any other measurement people are tossing at you for flashlights. Brightness really does count. And you don’t need a million lumens most of the time. You just don’t.
Day to day, doing this job, ninety lumens is about where I set the minimum. Ninety lumen and above works for most of us. Don’t go broke buying a flashlight trying to get 100,000 lumens!

Everything I’m talking about here you can get in ten-dollar, twelve-dollar, or sometimes seven-dollar flashlight. Keep it affordable. You’re going to use it a lot, but that doesn’t mean it has to be super expensive.

2. Batteries

What kind of batteries do you want in a flashlight?

I’ve been in the game long enough that I used to carry that big, long stick of a flashlight that was loaded up with, what, six or eight D-cell batteries.

We all pretended it was just a flashlight, but in a pinch, we’d give someone a smack with it if we had to. Purely in self-defense of course. (Always keep things legal and ethical.)

Nowadays, the batteries can even be rechargeable through a usb-port or by plugging it into a wall. I don’t have a ton of experience with those. I know guys that do, and they love them. I have no problems with that in particular. What little I’ve worked with them rechargables have really worked well for me.

Security Guard Training Note: For my brothers and sisters in security… if you’re using your flashlight a lot every night, rechargeable may be the way to go. Purchasing batteries is very expensive.

For a lot of us private investigators and process servers who use flashlights more intermittently AA batteries is the way to go. Why? If you use a flashlight with AA batteries, when push comes to shove and we’re facing a zombie apocalypse, you can find AA batteries everywhere. Pull them out of a remote control if you have to. If your batteries die, you’ll have a light source, because you’ve chosen a common battery. If you choose those button batteries or something like that, they’re expensive to replace and hard to find in a pinch.

3. Size of Flashlight

For security professionals back in the day, we used to carry those big, huge flashlights. Nowadays, flashlights can be pretty small. I kind of like that.

The flashlight I carry regularly is not very big. (Only about 7 inches long. But… it’s very bright.

It’s got the ninety lumens (plus) that I’m looking for. And it’s got a one-touch button on the back to operate it.

This fits very easily into tactical pants pockets, and even in a back jean pocket if you need to.

I have lost one or two of these over the years carrying them in the back pocket of my jeans, especially the ones that have a little clip on them. I like the pocket clip, but they’ll catch on something and I’ll lose them. But, for ten dollars, you can’t go wrong. Snag two and you’ll have a spare one for when you lose the one you’ve got.

That size of flashlight is really good for security guards. If you’re carrying a flashlight daily, as a private investigator or a process server – and I really believe it’s one of the very few things you need to carry with you on a daily basis for the job – then I like a very thin, pen-like flashlight. Those are generally going to use AAA batteries and I don’t have a problem with that. We’re talking about something you can slip into your jacket pocket. You can carry it around as easily as an ink pen and have readily accessible whenever you’re working.

It’s very important, though, to carry that flashlight. Even when you don’t think you’ll need it. You’d be surprised how often it comes up.

4. Functions

Last but not least, there are all sorts of functions and features on flashlights that are really nifty and fun to have, but it begins to fall into that “toy” category.

The flashlight I carry just has a push on, push off button.

When I press it, I know it going to turn on with a steady, high power beam. When I press it again, I know it’s going to turn off.

I don’t have to worry that it will turn on in a “flashing” mode or low power or red.

Every once in a while, a special function comes in handy. But, honestly, if you need it to flash you can just cover it with your hand, wave it back and forth, or turn it on and off manually on the very rare occasions you’re going to need it. Very rare occasion.

5. Tactical Consideration

For tactical brothers and sisters in security, especially those that carry firearms, a momentary on / momentary off switch is very nice.

You can turn your light on and off at will. That’s because, when you’re holding a flashlight and a firearm at the same time and moving tactically, you want to be able to shut off that light quickly so you’re not illuminating yourself to the bad guy. The you want to turn it back on instantly to illuminate him and his location. A momentary touch switch allows for that.

Personally I work unarmed so I greatly prefer click on / click off. In day-to-day security work, we generally want to turn on the flashlight and not worry about positive pressure on the button to keep it on. Being able to turn it on and knowing it’s going to stay on is valuable to me.

6. Brightness Levels

Some flashlights do have different brightness modes like low, medium, and you can use these to extend the battery life. I don’t really find the need for that. I want, reliably, I push the button once and here’s what happens. No question.

7. Size of Beam

It is a nice feature to be able to focus the beam of light to the size you like to work with and this can change based on the work your doing. Most flashlight seem to have that feature and it’s probably the only “bells and whistles” type of thing I like on a flashlight.

What do you think?

That’s a lot of information about flashlights, but, really, these are the fundamentals. When you learn more about flashlight, keep these things in mind. These are the really important fundamentals.

In our industry, those of us who are really out there doing it in security and investigations, we’ve each got the flashlight we like and we know that we’re right about it! 🙂 So, please, share with me any comments, ideas or suggestions. And while there’s twenty-five plus years of experience that goes into my evaluation about what makes a good flashlight, I really want to hear from you as well.

I love to learn new things too!

Committed to your success and safety
Larry Kaye,
Private Investigator (Ret.) &
#1 Best Selling Author

P.S. – For Bouncers and Doormen… you may want a flashlight with ultraviolet (UV) light for checking I.D.s. But, of course, there are really all sorts of specialty consideration in the security and investigations profession.

P.P.S. – And, of course, don’t miss my special report titled… If You Want To be a Private Investigator Give Up… Unless You Do These Three Things. You can get it right here…

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