Open and bi-hexagonal ends with 15° offset for greater access. Hardened and tempered, drop-forged chrome vanadium. High quality fully polished finish. Ultra-strong ballistic nylon storage roll. Includes sizes 1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8", 11/16", 3/4", 13/16", 7/8", 15/16", 1 and 1-1/4".