Old Part Numbers: SSF-3158-1This is the screw that holds down the piston cover, on the top of the piston.

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.

Screw, #10-14 x 2.50". This is the screw for the air intake muffler cover (2 used).

Screw (fastener) for the motor/pump shroud.

Old Part Numbers: PG0250300BK, S1151Air compressor pressure gauge, 1/4" male NPT back-mount, 300 PSI, 2" face. Remember to apply plumber's tape to the threads.