Surface pumps cover an enormous range and variety, but for simplicity they are characterised into two divisions namely: Centrifugal and Positive Displacement.  By far the most common type of pump and the one usually thought of as a surface pump is the Centrifugal Pump.  

Centrifugal Pump rotates are utilising centrifugal force and they are commonly used either to pressurize water from an atmospheric tank, to deliver purified water to a specific point of use, or simply to increase pressure when required.

The built-in pressure switch is set for 60 psi off and 40 psi on. The pumps come with straight threaded male half-inch fittings that snap into the quick disconnect ports. The optional strainer is highly recommended to keep debris out of the pump, insuring long diaphragm life.