Extension Wrench To easily reach bolts and nuts in hard-to-reach places. With this handy tool, you can, for example, loosen a nut from a fan or pulley at the front of the engine without having to contort yourself between the engine and radiator and struggle with limited free play. You simply attach the ratchet to the top connection and the socket to the bottom, and with every turn made at the top, the bottom connection will rotate along by means of the internal chain connection. Indispensable for every mechanic / hobbyist! Specifications: Length: 390 mm. Thickness: 21 mm. Hole size on both sides: 3/8" Adapter sizes (included): 3/8" - 3/8", 3/8"-1/4", 3/8"- 1/2" Max torque: 53ft/lb 71.87 Nm Material: steel Chain-driven