Wera 05066525001 867/1 Z 1/4'' Hex Torx BO Insert Bits are for recessed TORX® screws. The bore hole in the bit and the pin in the TORX® BO screw prevent any unauthorized loosening - secure fastening. Tough viscous for universal use. Wera 867/1 Z 1/4'' Hex Torx BO Insert Bits are suitable for holders as per DIN ISO 1173-D 6.3.