This bosch square extra hard robertson screwdriver bit is supplied in an r1 square tip size, 50mm length, in a pack of 3. The longer 50mm length provides greater reach for recessed fixings, deep countersinks, or applications where a standard 25mm bit simply cannot gain adequate access. The r1 tip is suited to smaller robertson-head screws. Manufactured from s2 modified steel with an optimised heat treatment process, this bit delivers extra-hard quality for consistent performance across all screw-driving tasks. The tapered torsion zone absorbs force and vibrations, coping easily with torque peaks during use. The 1 4 external hex shank ensures a strong, secure fit in three-jaw chucks and 1 4 internal hex tool holders. Features and benefits: s2 modified steel with optimised heat treatment for extra-hard, long-lasting durability tapered torsion zone absorbs force and vibrations to handle torque peaks effectively 50mm length provides extended reach for recessed or deep fastening applications 1 4 external hex shank for maximum torque transmission and a secure connection compatible with screwdrivers and drill drivers specifications: tip type: r1 square robertson length: 50mm shank: 1 4 external hex pack quantity: 3 contents: pack of 3