This primary standard Range are designed to test, adjust and calibrate measuring instruments, mechanical or electronic pressure by comparison (pressure gauges, pressure transmitters or sensors or switches) The dead weight tester consist of a pressure generator connected to a compressed air source, a piston/cylinder unit, a set of weights identified. The capstan can adjust the pressure by the gas through the piston. This pressure is balanced by the piston / cylinder which compares the instrument to calibrate the values of pressures generated by the standard. These reference instruments are used in factory or calibration laboratory. They are robust and easy to use and have a high longterm stability