Premium S2 steel construction: it is shock-resistant, tough, and maintains its shape with heavy use, outperforming Chrome Vanadium and lesser alloy steels Hex end features chamfered edges for easy insertion onto fasteners Ballpoint end for hard to reach areas, allowing up to 25-degree entry angle Flexible single piece storage case opens flat for easy access, and latched when folded for easy carry and storage 9 SAE Sizes: 1/16, 5/64, 3/32, 1/8, 5/32, 3/16, 1/4, 5/16, 3/8 inch