Tekton micrometer torque wrenches are designed to instill confidence in the wrench's accuracy and control during operation. Each wrench is calibrated to be accurate within ±3% for both clockwise and counterclockwise directions and certified to the ISO standard for the full listed range, unlike torque wrenches calibrated to ASME standards, which do not require calibration below 20% of the listed range. The single half-moon pawl maintains 9 teeth engaged with the gear at all times, so it won't skip under stress. The internal components are the same design and construction as all of our 90-tooth ratchets. The 4-degree swing arc reduces the length of travel at the end of the wrench handle between each click. The micrometer scales are laser-marked in bold fonts on the satin-finished handle body, making them easy to read. The collar springs into a locked position that holds your setting and prevents accidental movement during operation. There is no thumb knob to tighten at the end of the handle. A deep, sharp-cut diamond pattern on the surface of the handle creates a coarse texture that won't slip in your hand. The case provides safe transport for the torque wrench and protects it from drops. This set includes 1/4 in. drive (20 - 200 in-lb), 3/8 in. drive (10 - 100 ft-lb), and 1/2 in. drive (40 - 200 ft-lb, 40 - 300 ft-lb) micrometer torque wrenches, each one coming with its own case and serialized certificate of calibration. Material: Chrome-Plated Steel.