Combination spanners offer the convenience of open-ended at one end & the high-torque of the ring spanner at the other. These 11-piece sets cover a wide range of Imperial sizes (see below). Forged from chrome vanadium steel hardened, tempered & chrome plated for corrosion protection. Imperial AF sizes 1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8", 11/16", 3/4", 13/16", 7/8”