Alltrade Tools' Powerbuilt Digital Torque Adapter converts regular ratchets to a digital torque wrench and calibrates other torque wrenches. The tool is accurate within 2 percent and offers five measurement settings, including Nm, ft./lbs. and in./lbs. The adapter measures and records both peak and trace torque, and comes with a calibration device and carry case. Available in 3/8"- and 1/2"-drive versions.