Pressure relief valve with grease return and pressure gauge. The return line carries the excess sweat back into the syringe for easy disassembly of the nozzle without a mess. Manometer for reading of current pressure graduation 0-1000 bar. The equipment is mounted on recommended grease guns. Working pressure 500 bar. Max pressure 700 bar. Handles grease up to penetration class NLGI 3. Connection thread hose internal 1/8".