Professional screwdriver bits with hardened core and torsion zone for extra strength, durability, and optimal grip. Special features: Hardened core for extra strength and longer life. Flexible torsion zone absorbs torque peaks and reduces the risk of breakage (Torsion bits only). "Extra Grip" ribs reduce the risk of slipping. Professional quality, including Torsion shank and Torsion with "Extra Grip" ribs. Technical data: Type: Quick-release bit holder. Magnetic: Yes. Supplied as standard: 1 piece (screwdriver bit).