[The pressure input is 1/4F] The water pump pressure is adjustable thanks to this pressure switch and you can adjust the adaptable pressure according to your needs. It is important to know that the pressure input dimension is not the same for all the pumps. The pressure input nut of this pressure switch is 1/4F. [easy to adjust] This pressure switch has a fitting, a nut and a ring. Remove the nut and the ring that will not be used. Screw the fitting into the pressure switch then screw the pressure switch on the pump. It could not be possible if an element of the pump blocks the rotation. Provide an adapter and finally it works well. The pressure switch whose pressure input nut freely rotates around its axis to the total tightening. [Automatic control] This pump pressure switch will automatically activate the pump when the pressure is below the defined threshold of the switch, and will automatically stop the pump when the pressure is higher than the defined threshold. [high quality