3/8-inch hex bit set. Chrome vanadium alloy steel construction for strength and durability. Hardened alloy steel bits. Polished nickel chrome plated finish. Lifetime warranty. SAE hex socket sets include: 1/8", 9/64", 5/32", 3/16", 7/32", 1/4", 5/16" and 3/8" sockets. Metric hex socket sets include: 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm and 10 mm sockets.