The Wera premium bits for TORX socket screws. TORX BO screws have a protruding pin in their drive profile. This prevents unauthorized loosening, as these screws cannot be operated with "normal" TORX tools. Only special TORX BO tools have a bore which can mount the pin. Tough, for universal use. 1/4" hexagonal, suitable for holders as per DIN ISO 1173-F 6.3.

For recessed TORX® screws with securing pin
TORX® bit with bore hole on the output side
Ductile and tough for hard materials
1/4" hexagon drive (Wera connecting series 4)

TORX® socket screws with safety pin (BO = with bore hole) Drive 1/4" hexagon, suitable for DIN ISO 1173-F 6.3 bit holders Design TORX® with bore hole, tough, for universal use