Click-type, mount for interchangeable insert tools 9x12, QuickRelease safety lock, rapid setting, dual stop signal, twin scales Nm/ft.lb, the measuring element is only under load while force is being applied, no.need for manual reset to zero can be applied for either clockwise or anticlockwise tightening by turning the inserts over any force applied to the tool after the 'click' or applied in the opposite direction to the current function - e.g. forcible loosening of a jammed screw - does not act on the trigger mechanism and cannot cause damage to it. Calibration using perfectControl calibrating unit no.7794 or calibration system no.7706. Adjustment without disassembly. With certificate. Display deviation value ± 4%.