This Bosch Hex Extra Hard Screwdriver Bit is sized at Hex 4mm and measures 25mm in length, supplied in a pack of 3. The 4mm hex size handles a broad range of medium fastening tasks with confidence, and the 25mm length is ideal for standard screw-driving work where a compact, manageable bit is preferred. Crafted from S2 Modified Steel and treated through an optimised heat treatment process, the bit delivers extra-hard quality that holds its edge over time. The tapered torsion zone absorbs the force and vibrations generated during screw-driving, managing torque peaks effectively to reduce bit wear and protect fastener heads. The 1/4" external hex shank provides a dependable connection in three-jaw chucks and ¼" internal hex tool holders, making it a versatile fit for screwdrivers and drill drivers. Features and Benefits: • S2 Modified Steel with optimised heat treatment for extra-hard durability • Tapered torsion zone absorbs force, vibrations and torque peaks • 1/4" external hex shank for strong connection and maximum torque transmission • Compatible with three-jaw chucks and ¼" internal hex tool holders Specifications: Hex Size: 4mm Length: 25mm Pack Quantity: 3 Contents: • Pack of 3