This WARRIOR Nut and Bolt Extractor Set is constructed with reverse spiral flutes to securely grip damaged or rounded nut or bolt heads for easy removal. The set includes the following sizes: SAE: 3/16 in., 1/4 in., 5/16 in., 3/8 in., 7/16 in., 1/2 in.; Metric: 8 mm, 10 mm, 11 mm.