Our innovative 6 point flank drive holds onto fasteners and prevents any rounding off corners. This means your fasteners are protected and so are your sockets. Unique design grips the flat sides of fasteners rather than the corners to offer security and prevent stripping/ rounding off of bolts; Drive Size: 1" High-contrast visibility permanent laser etched size markings are easy-to-read in low light for easy retrieval & identification Package Content: 16pcs Impact Socket (1 5/8", 1 11/16", 1 3/4", 1 13/16", 1 7/8", 2", 2 1/8", 2 3/16", 2 1/4", 2 3/8", 2 1/2", 2 5/8", 2 3/4", 2 15/16", 3", 3 1/8") From trucks and tractors to heavy equipment and large machinery, big service and repair jobs need the 1-inch Drive Impact Socket Set. Made for use with impact wrenches, these premium industrial sockets deliver superior performance. High-torque, 6-point design contacts and grips the stronger flat sides of fastener head, not the weaker corners, to prevent stripping or round-off under extreme stress