Surface drive plus provides stronger grip on fasteners nearly eliminating fastener rounding. Oval shaped beam provides improved comfort. Ratcheting box end needs as little as 5 degrees to move the fastener. Thin head shank design allows for work in tight spaces. GrearWrench products are warranted for life to be free of defects in material and workmanship The XL ratcheting set is 20 percent longer, to access the hard to reach fasteners. The surface drive provides a stronger grip on fasteners, eliminates rounding of fasteners and delivers up to 25 percent more torque. Its comfort has been improved with the sleek, oval shaped beam. The set includes 1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8", 11/16", 3/4", 13/16", 7/8", 15/16", and 1".