Heat treated and hardened with a fully polished mirror finish. Chrome Vanadium steel 3/8"Sq Drive x 12-Point WallDrive® rings. Minimum/maximum length: 65/70mm. Ideal for use with torque wrenches (please note: a setting adjustment is required to compensate for the increased length of leverage when using these torque adaptors). Suitable for limited access applications. Supplied in an EVA storage tray. Tray Size (W x D x H): 185 x 185 x 32mm.