1. Pressure Adjustable:The water pump pressure is adjustable through this switch and you can set the adaptable pressure as you the work needs. 2. Pressure Control:This is a water pump pressure control switch for perfect pressure control. Easy to install, can be used for a long time. 3. Durable Material:Our water pump pressure control switch is made of high quality materials, it features strong strength and long durability. 4. Fit for :Suitable for most of water pumps, such as self-priming water pump, Automatic pumps, injection water pump, jet pumps, garden water pump, clear water pumps, etc. 5. Instructions；1 phase or 3 phase (15 or 230 volt / at 115 volt 1 phase it will handle 1.5 hp, at 230 volt 1 phase it will handle 2 hp, and at 230 volt 3 phase it will handle 3 hp.). Preset on pressure: 20 psi/ the contacts close at this pressure to send power to the motor/ pump. Preset off pressure: 40 psi/ the contacts open at this pressure to shut power off to the motor/ pump. 15 or 230 volt / at 115 volt 1 phase it will handle 1.5 hp, at 230 volt 1 phase it will handle 2 hp.