Air compressor check valve. 3/8" Comp x 1/2" MPT with 1/8" FPT side port.  The check valve is a one-way valve that prevents air from back-feeding from the air tank. If your unit has a hard time restarting when trying to cycle or your pressure switch...

Order this if ordering valve plate or a new head.

Old Part Numbers: D20763, D27254, D206434-Port OEM regulator. The Regulator controls the amount of air to your hose. Replace this if you're not able to adjust the PSI to your hose or if it leaks.   

Old Part Numbers: SSW-7367Strain relief for air compressor power cord.

Old Part Numbers: AC-0558