Ruland TW:BT-4C-3/8-XX-LBS-FT is a T-handle slip type torque wrench with with a 3/8" square drive size. The torque is preset at the factory and the user must choose the desired torque during the purchasing process which can be 4.17-33.33 lbs-ft for this wrench. During opertaion, once reaching the specified torque the wrench automatically releases and resets. This prevents tightening above the preset value, even with continued turning. The T-handle profile alllows the user to easily grip the torque wrench and rotate by hand. TW:BT-4C-3/8-XX-LBS-FT is manufactured by Seekonk Precision Tools in Massachusetts from chrome plated alloy steel for durability and longevity in industrial environments. It is made in accordance with Federal Specification MIL-STD-45662A and comes standard with an NIST traceable certification. Periodic calibration is required depending on frequency of use.