Precautions for use: 1. Cannot be soaked in water 2. The pressure adjustment screw cannot be adjusted. Before leaving the factory, the pressure has been adjusted, any adjustment will increase the return pressure, causing the water pipe to burst easily 3. The water inlet must be installed with a filter device to prevent impurities from entering. Otherwise, it is easy to block the pump, causing the pressure to drop or even unable to discharge water 4. Not resistant to oil corrosion.