for Torx®-screws VDE tested, safe for work up to 1000 Volt AC or 1500 Volt DC with blade diameter tapered towards the tip, for deep-set screws fast-turning zone and slip protection for thumbs and index fingers, secure grip for use in the hand color coded by screw type, quick identification special alloy based on spring steel, exceptional elasticity coupled with with high hardness for your safety: VDE interchangeable blades may only be used with PB Swiss Tools VDE interchangeable handles!