The Crescent X6™ Pass-Thru® Ratchet & Socket Set is a unique pass-thru socket and ratchet system that eliminates the need for deep sockets. Every Pass-Thru® ;socket replaces one standard and one deep socket. The universal design allows it to fit 6 fastener types: Hex, Square, 12 Pt., E-TORX , Rounded Hex and Spline. The ratchet is up to 40% stronger than standard ratchets. With a 5° ratcheting arc that provides great fastening ability in restricted areas. Up to 50% thinner than standard ratchets for greater access. The supplied adaptor converts the X6 to a standard ratchet for traditional square drive sockets. Contains: 9 x Metric X6™ Pass-Thru® Sockets: 10, 11, 12, 13, 14, 15, 17, 18 & 19mm9 x Imperial X6™ Pass-Thru® Sockets: 3/8, 7/16, 1/2, 9/16, 5/8, 11/16, 3/4, 13/16 & 7/8in1 x X6™ Pass-Thru® Ratchet1 x X6™ Pass-Thru® to 1/2in Sq Drive Adaptor