Tamper-proof screws Screws that cannot be easily removed unless a special tool is used. They are effective in preventing theft, disassembly, mischief, information leakage, accidents, etc. They are used to protect hazardous parts such as playground equipment, window shields, attractions, toys, switch boards, as well as security parts and expensive equipment. Torx, one side, no recess, two-hole, tri-wing, with pin, Fujiyama, TRF and the like are available.