XSR Step Reamer Set Features 3 piece set with 15 sizes hybrid between a step drill and reamer enlarge and align hols in steel up to 1/2 inch thick ideal for cutting bolt hole sizes for a variety of industries engineered for heavy duty applications safety collar prevents over penetration fast cutting, long tool life and bur free holes 3/8 inch flattened shank for use with power drill or drill press specifications: XSR-5/16x9/16 sizes 5/16, 3/8, 7/16, 1/2 and 9/16 inch XSR-9/16x13/16 sizes 9/16, 5/8, 11/16, 3/4 and 13/16 inch XSR-13/16x1-1/16 sizes 13/16, 7/8, 15/16, 1 and 1-1/16 inch
