3/8" DR Micrometer Torque Wrench 20-100 Ft/Lb On these types of torque wrenches, the desired torque is determined before carrying out the operation, and when the setpoint is reached, a clicking sound is produced, which can also be felt by the hand, indicating that the desired torque has been attained. When you stop applying torque, the torque wrench is already prepared for a new operation. It has calibrated scales in SAE and metric systems that are laser-etched on the handle. These are shown horizontally on the shaft and vertically on the handle so you can set the required torque. Being designed for continuous use, it is an excellent precision tool for applying specific torque values. Every part is made with tempered steel to resist wear. The external parts are nickel-chrome coated to prevent rust. The position of the ratchet?s head lever allows ratcheting clockwise or counter-clockwise, and a fixed position by setting the lever to the center. Two-fold protection: The exclusive internal design minimizes the required effort, decreases friction, prolongs the torque wrench life, allows accurate calibration and retention of settings. 3% precision on clockwise direction, from 20-100% of its scale.