Changeable piston type valves ensure prefect sealing. Both high pressure gauge and low pressure gauge are support to readjusted to the zeropoint. The manifold gauges are marked with temperature and pressure scales or are equipped with interchangeable refrigerant scales. You can have a try. Packing List: 1 * Refrigeration Guage 3 * 1.5m Hose 1 * Can Opener 2 * Connection Adapter 1 * Hook 1 * Bag of Fittings 1 * Plastics Box