Stainless Steel Security Screws

Stainless steel security screws are tamper-resistant screws that resist oxidation and deterioration. Stainless steel contains chromium which when exposed to oxygen forms a chromium oxide layer which seals off the internal metal from oxygen to prevent rusting.  The head of the screw can only be fit with a non-standard driving bit to prevent tampering.

Security screws resist tampering, vandalism and theft.  Stainless steel security screws are usually machine screws or used in fastening sheet metal.  Wood security screws are less common. Head styles are commonly pan, truss or button, and self-tapping security screws are available.

Simple security screws can have a one-way slotted head that accepts a flathead driver but only allow the screw to be driven in. More complicated versions use a pin or post in the middle of the head that only allow driver bits with a corresponding cut out in the driver tip to fit. You might have seen tamperproof Torx head screws like this - standard Torx drivers won't fit them.  Getting even more complicated are snake-eyes heads, like what's in the image on this page.

For even more security, screws can be designed so the head snaps off when torqued a certain amount.​  Then no head exists to use to drive the screw out.

Names you'll see for security screws are pin head, reverse thread, tri-wing, one-way, ​tamperproof, security or breakaway.

Unique Security Screws

As more security screw drivers have been sold, with little control over who they're sold to, the security of the screws they turn has obviously decreased.  Manufacturers have responded by creating new proprietary screw head designs and tightly controlling the driver sales.  You are now able to buy screws and drivers that are unique to you, so that no other drivers exist that fit that screw (of course that doesn't prevent using other tools to break the screw).

Sources of security screws include Bryce Fastener, Tamperproof Screw, and Tufnut.