The Draper 63537 sockets are manufactured from chrome vanadium steel, which is correctly hardened and tempered to ensure a durable, hard wearing product. Each socket has a knurled ring for extra grip, and this set is also supplied with a 72 tooth reversible soft grip ratchet and accessories. This set includes: 1/4\" sockets; 4, 4.5, 5, 5.5, 6, 7, 8, 9, 10, 11, 12, 13mm, 1/4\" deep sockets; 4, 4.5, 5, 5.5, 6, 7, 8, 9, 10, 11, 12, 13mm, 1/4\" extension bars; 50, 100, 150mm, 1/4\" sliding T bar 1/4\" coupler 1/4\" (F) - 3/8\" (M) adaptor Spinner Handle 3/8\" sockets; 10, 11, 12, 13, 14, 15, 16, 17, 18, 19mm 3/8\" deep sockets; 10, 11, 12, 13, 14, 15, 16, 17, 18, 19mm 3/8\" extension bars; 75, 200mm, 3/8\" spark plug sockets; 10, 12, 14mm 3/8\"( F) - 1/4\"( M) adaptor 3/8\" (F) - 1/2\" (M) adaptor 3/8\"( F) - 1/2\" (M) Sliding T-Bar Adaptor 1/2\" sockets; 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 30, 32mm 1/2\" deep sockets; 17, 18, 19, 21, 22, 24, 27, 30, 32mm 1/2\" Sq. Dr. extension bars; 75, 250mm, 1/2\" (F) - 3/8\" (M) sliding T-bar adaptor (forms a sliding \'T\' bar when used with an extension bar) 1/2\" (F) - 3/8\" (M) adaptor Universal Joints; 1/4, 3/8 and 1/2\" Sq. Dr. Flexi Extension; 150mm 1/4, 3/8, 1/2\" 72 tooth reversible ratchets with soft grip and quick release button