05380158001 Wera 851/1 RH 1/4'' Hex Phillips ® Insert Bits are high quality bits for phillips screws with reduced shaft diameter for low-lying screw connections. Wera 851/1 RH 1/4'' Hex Phillips ® Insert Bits are desighed for the countersinking of screws without any surface damage and are tough and viscous for universal use. Wera 851/1 RH 1/4'' Hex Phillips ® Insert Bits are suitable for holders as per DIN ISO 1173-D 6.3.