Full interface with Proto® Interchangeable Head Attachments. Accuracy of +/- 2% of indicated value in both clockwise and counter clockwise directions. Broad accuracy range extends from 10% to 100% of Full Scale to help reduce the number of torque wrenches required. Ninety-nine "on-board" memory storage locations help improve efficiency when taking multiple torque readings. Three units of measure are available (Ft-lb, In-lb, and Nm).