Expert Quality, insert bits manufactured from S2 silicon steel, hardened and tempered with shot blasted finish. Bit holders made from chrome vanadium steel hardened, tempered and chrome plated. Draper 40 Piece Bit Set With Case Expert Quality, insert bits manufactured from S2 silicon steel, hardened and tempered with shot blasted finish. Bit holders made from chrome vanadium steel hardened, tempered and chrome plated. Spare bits are available. Packed in steel case Contents: 1 x Bit holder 10mm hexagon x 3/8" sq. drive 1 x Bit holder 10mm hexagon x 1/2" sq. drive 7 x Draper TX-STAR® bits, 30mm: T20, T25, T30, T40, T45, T50, T55 7 x Draper TX-STAR® bits, 75mm: T20, T25, T30, T40, T45, T50, T55 5 x Spline bits, 30mm: 5, 6, 8, 10, 12mm 5 x Spline bits, 75mm: 5, 6, 8, 10, 12mm 7 x Hexagonal bits, 30mm: 4, 5, 6, 7, 8, 10, 12 7 x Hexagonal bits, 75mm: 4, 5, 6, 7, 8, 10, 12mm