The reverse thread of the extractor is designed to engage and provide maximum grip. Suitable for both hand tools and power tools. The 27PCS easy-out extractor set contains: 7/8", 27/32", 13/16", 25/32", 3/4", 23/32", 11/16", 21/32", 5/8", 19/32", 9/16", 17/32", 1/2", 15/32", 7/16", 13/32", 3/8", 11/32", 5/16", 9/32", 1/4", 7/32", 3/16", 5/32", 1/8" for all your needs!