• TAMPERPROOF: The "Proof" is in our name.

    Manufacturers of the Snake Eyes spanners. All made in the USA.

    Also stocking Phillips Pin-Heads, Torx and Socket Pin-Heads,

    Tri-Wings, Opsit, One-Ways, and our exclusive TP3.

  • We specialize in stainless steel screws.

    Eight styles of tamper-resistant fasteners in over 1000 sizes.

  • Family owned and operated since 1983

Free UPS Ground shipping on all first-time TP3 orders over $100


Tamperproof was the first company to refer to the two-hole drilled spanners as the “Snake Eyes”. That began over 40 years ago. The name derives from the casino game “craps”: When one rolls the two dice and gets a “1” and “1” on each die, that’s called “Snake Eyes”. When we began selling the spanners we found that buyers, when explaining the type of screw they wanted, would often tell us “You know, the ones that look like Snake Eyes”.

What makes Tamperproof’s Snake Eyes® spanners distinctive is that the 2 spanner holes are drilled. The drilled spanner holes allow a tight fit with the matching tools. Other manufacturers usually punch the holes in the head when the screw is being cold-headed. This makes the fit of the matching tool less secure and the driver bits can slip off. So though they may call them “Snake Eyes” they are not necessarily the same product. Only Tamperproof offers the original SNAKE EYES ®.