The Wera 05136302001 840/4 Z SB 1/4” Drive Hex Socket Bit are tough viscous Wera bits for hexagon socket screws and universal use. Hex-Plus 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-D 6.3.