The purpose of B107.300 is to define essential performance and safety requirements for three types of torque instruments - (a) manually operated torque instruments, commonly used for mechanical measurement of torque for control of the tightness of threaded fasteners, (b) for electronic torque testers used for checking manually operated hand-held torque wrenches and screwdrivers and (c) for manually operated electronic torque instruments with integral or interchangeable heads. It includes requirements for endurance, torque value ranges, and accuracy for these torque instruments. It specifies test methods to evaluate performance related to the defined requirements and safety, and indicates limitations of safe use.