6.3 mm (1/4″) square drive. With forged, tempered hex inserts. Chromium-vanadium steel. Chrome-platedContents:1 reversible ratchet (72 teeth) with disc switch1 hex socket bit ea. in AF 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 mm1 handle with sliding collar 115 mm1 extension ea. in 55, 148 mm1 universal joint1 socket bit ea. for screws with hexagon socket profile in AF 3, 4, 5, 6, 8 mm1 socket bit ea. for screws with External TORX® profile in E 4, E 5, E 6, E 7, E 8, E 101 socket bit ea. for screws with Internal TORX® profile in T 8, T 9, T 10, T 15, T 20, T 25, T 27, T 301 handle with square drive