This 10 Pieces Triple Square Spline Bit Socket Set, which Include: 1/4 inch Drive: 4mm, 5mm, 6mm; 3/8 inch Drive: 8mm, 9mm, 10mm, 12mm, 14mm(tamper proof); 1/2 inch Drive: 16mm(tamper proof), 18mm(tamper proof). The length of this triple square spline bit socket is 4 inches. The Bits is made of premium S2 alloy steel for superior hardness that reduce wear-outs and insure , the precisely machined bit tips to accurate size, chamfered bit ends insert smoothly into fasteners and protect both bits and fasteners from damaged edges. Also the -V steel sockets superior for greater turning power with mirror chrome finish for corrosion resistance. This set is included with a durable blow-molded storage case. Colour:Silver Material:steel Size:22 x 5.5 x 13cm Package Contents: 1 set * Tip Bit Socket Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.