The Wera 05135092001 840/4 Z 1/4” Drive Hex Socket Bit is a tough viscous Wera bit for hexagon socket screws for universal use. The Hex-Plus profile offers a greater contact surface in the head of the screw. The notching effect is therefore reduced to a minimum and damage to the screw head more or less eliminated. 1/4” hexagon, suitable for holders as per DIN ISO 1173-F 6.3.