Powerbuilt sockets are strong chrome vanadium steel with polished chrome plate or durable impact-rated Chromoly steel with a black phosphate finish. They mate to fasteners easier with precision chamfered hex faces and with the patented Z-Drive 6-point hex pattern turn the flat surfaces to reduce rounding. Deep or shallow sockets have high visibility sizing and deep center holes for longer bolts for added functionality. Dependable Powerbuilt sockets meet or exceed ANSI standards and have a lifetime warranty.