Wera 840/1 ZBO Hex Pinned Security Bit Extra Tough

This Wera 840/1 ZBO bit is supplied in a 4mm hex size with a 25mm length, a highly practical size for medium-format hexagon socket BO security screws commonly encountered in plant equipment, fabrication work, and mechanical assemblies. The 4mm drive provides a firm, positive engagement with tamper-proof fixings that standard hex tools cannot shift. Wera's Hex-Plus profile delivers a greater contact surface within the screw head, greatly reducing the chance of cam-out or rounding — a common issue with conventional hex bits. The extra tough specification ensures this bit performs consistently even when working with harder materials or under sustained torque. Features and Benefits: • 4mm hex size suited to medium-format security BO fasteners • Hex-Plus profile reduces cam-out and protects screw head integrity • Extra tough construction withstands hard materials and high-torque use • 1/4" hexagon drive compatible with DIN ISO 1173-D 6.3 holders Contents: 840/1 Z Tamper-proof Hex-Plus BO bit, 4 x 25mm Specifications: Hex Size: 4mm Length: 25mm Drive: 1/4" hexagon Pack Quantity: 1