14pc Power Nut Driver Set. SAE sizes include; 3/16, 1/4, 9/32, 5/16, 11/32, 3/8, and 7/16 inch. Metric sizes include; 5, 5.5, 6, 7, 8, 10, and 12mm. Bit holder has a belt loop. 1/4 inch hex shank for use with Drills and other tools that accept 1/4 inch hex bits.