Master Bit Socket Set (88-Piece)The Capri Tools 88 Piece Master Bit Socket Set is a complete collection of most frequently used bit sockets. We use premium S2 steel tempered with our proprietary heat treatment process to make these bits (other than 1 2 in. drive hex bits 9 16 in. 14 mm and above). They are exceptionally durable and strong, withstand high torque and do not twist, protecting both the bit and the fastener. The 1 2 in. drive hex bits 9 16 in. 14 mm and above are forged