Manufactured from chrome vanadium steel. 65mm long 1/4″ & 3/8″ square drive & 72mm long 1/2″ square drive. 1/4″ hex, drive quick change shank. Ideal for use with the Amtech 18V V6515 cordless combi drill [26Nm torque] or the Amtech 18V V6520 Impact driver [100Nm torque]. Note: This product is not Impact Grade therefore not suitable for use with high torque Impact Drivers. Sizes:  1/4″ x 65mm. 3/8″ x 65mm. 1/2″ x 72mm.