The Titan Tools 16141 9-Piece Low Profile Impact Metric Hex Bit Socket Set includes (4) 1/4-Inch drive and (5) 3/8-Inch drive bits and (1) steel storage rail. The sizes for 1/4-Inch drive bits are 6, 7, 8 and 10mm and the sizes for 3/8-Inch drive bits are 12, 14, 17, 18 and 19mm. The low-profile design is for use in compact spaces. The Impact grade construction for use with impact drills. This low-profile impact metric hex bit socket set is made in Taiwan.