Torque wrench testers are measuring tools specially used for testing and calibrating torque wrenches and screwdrivers. The core part of the product adopts the microprocessor technology and it takes a series of new technology such as digital filter, calibrating zero automatically, none-linearity compensation in the designing to achieve the features as quick sampling speed, precise measurement, anti-interference, and self-diagnosis. It has good performance and easy to use. Some types have the RS-232 interface to be able to transmit the data to the computer for intelligent handling and making the calibrating conclusion automatically.