Tamperproof Screws and Security Fasteners | What You Need to Know

What Are Tamperproof Screws?

When we took a look at the Klein 4-in-1 Torx Screwdriver we came across one of its more notable features. “Includes T7, T8, T10 and T15 tamperproof Torx pin bits,” the packaging told us. Off in the distance, we hear the intern ask, “What’s a tamperproof bit?” And, just like that, we have the subject for our next “Training the Apprentice” article. Tamperproof bits work on tamperproof screws. These security screws present at least some protection against unauthorized or undesired access…sort of.

Editor’s Note: Check out our best deck screws article to see our top picks.

What are Tamperproof Screws? Another Layer of Security

Let’s say you find yourself in a curious state over the inner workings of the DeWalt FlexVolt battery. And, impending electrical injury risks accounted for, you decide you’ll take a look inside.

Well, DeWalt, for reasons revolving around liability and warranty issues, probably doesn’t want you tinkering around in the battery’s guts with something pointy and metallic. So, when they assemble their batteries, they use tamperproof screws to hold the housing together.

DeWalt has a lot of company in this regard.

A tamperproof Torx bit, for example, looks like a standard Torx bit. Look more closely, however, and you see it has an indentation in the middle. This accommodates a tamperproof screw. The screw in our DeWalt battery pack has a small nub in the middle of the depression. That nub renders a standard Torx bit useless. The tamperproof bit, however, fits right around it.

Why Use Tamperproof Security Screws

The idea behind the tamperproof screw seems obvious, especially given the name. When you don’t want just any dum-dum who owns a screwdriver to be able to disassemble something, you use tamperproof screws.

These screws see a lot of use in places like airports, public parks, electronics, aviation equipment, etc. Is there something where unsupervised repairs or modification could take place? Is there a fixture that could be likely susceptible to vandalism or theft? Because tamperproof bits are less common, tamperproof screws add another minor layer of protection against, well, tampering.

What Are Tamperproof Screws?

Of course, tamperproof screws and bits come in myriad shapes and sizes. As patents expire for proprietary tamper-proof designs, bit manufacturers can begin to sell more of these tamperproof bits. At that point, the term “tamperproof” begins to become a bit of a misnomer. We’ve seen that happen already with the aforementioned security Torx screws. When any consumer can purchase security bits—the basis for disallowing easy tampering with a screw gets thrown out the window.

Have Tamper-proof Screws and Bits Become Useless?

In a word: No. Dozens of different, proprietary tamper-proof screws and matching bits exist on the market today. Because so many manufacturers make and patent them, the chances of a person having them all remain slim. You can still find unusual and uncommon security screws and bits.

With that said, security Torx bits don’t really stop anyone anymore. They also remain inexpensive—which is why we tend to see them used everywhere a manufacturer wants some level of tamper resistance on their products.

slotted one-way screws bathrooms separators
I remember (and still see) these from my high school days. They kept kids from removing the dividers in the bathroom…which we still managed to do….it’s a long story.


The average person probably won’t have too many tamperproof bits in their tool arsenal. As a result, the system still has merit as an extra layer of protection against vandalism, theft, or unauthorized tinkering. However, for those of you budding electricians and repairmen out there, it might not hurt to get your hands on some of the more common tamperproof bit designs.

If you’re a Pro who has any tips, tricks, or general knowledge to pass on tamperproof screws and bits, feel free to add a comment below!

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