What’s the name of this tamper proof screw ? (looking for screwdriver type)

screw-terminal

I'm trying to fix device witch contain tamper proof screw witch i'm unable to recognize. I have set of standard tamper proof screwdrivers but i'm unable to find any suitable.

Could someone recognize this screw and point me what's the name of it so i could search e-bay for right screwdriver?
unknown tamper proof screw
Regards

Best Answer

Looks like a triangle headed screw to me. I had to get a set of drivers for these a while ago. In this set are TA18, TA20, TA23 and a TA27 - Triangular Allen key perhaps?