air compressor pressure switch control valve is an instrument that integrates mechanical pressure sensing and precise open/close in a high-pressure application. It has the characteristics of simple operation, cost-effective, stable, and0.1 million serving cycles. In pressure switch manufacturer, 26 Amp LEFOO LF10 28-175 PSI air compressor, pressure switch, control valve with a 4 port connection manifold. The switch listed is a universal replacement pressure switch that replaces brands such as Furnas, Square-D, and more. This switch is equipped with an unloader valve, a four-port mounting manifold, and an on/off lever. This is similar to the regular 4 port pressure switch, but this switch is equipped with heavy-duty 26 Amp contacts to provide a longer-lasting switch in demanding applications. The four-port manifold gives you the option to mount in it any direction and also has the option to add a relief valve, gauge, or multiple air outlet ports. These Ports can also be plugged if not needed which is what makes this switch a great universal replacement pressure switch. The unloader equipped on this switch is used to unload the air pressure off the head of the compressor when the air compressor cut off switch shuts off, this way when it starts there is no pressure on the piston and the compressor is able to start load free. This valve usually has a 1/4" plastic or copper line that runs to the check valve or the head of the compressor. If your compressor does not have an unloader line then this valve can be left not hooked up and the pressure switch will still function properly.