Seven Piece Hex Bit Set - These bits are a must when dealing with a variety of automotive applications. All Bits are two piece construction and made from S-2 steel alloy. This Metric Hex bit set come packaged in a plastic rail and includes the following Metric sizes: 3, 4, 5, 6, 7, 8 and 10 mm for use with 3/8in. square drive ratchet. Made in China. One year manufacturer's warranty.