Head gasket (above the valve plate) for air compressor pumps. If the compressor pump doesn't seem to pressurize as quickly as it should or is leaking in between the head, valve plate, cylinder, or crankcase while running, there's a good chance you need...

If your valve is leaking on the side of the switch, do not order this part. Order check valve instead. 105-135 PSI RATING.    

Replace if misreading or broken.

Adjustable air pressure knob assembly. (Gauge sold seperately).

Air compressor power switch. Note: This switch has four wire terminals.