Air compressor check valve, 1/2" Compression x 1/2" MPT with 1/8" hole; plug hole if not needed.  https://mastertoolrepair.com/1-8-blk-steel-plug-s-h-100b6e/ If the small unloader (bleeder) valve on or under your pressure switch leaks constantly...

Old Part Numbers: 034-0184Replacement Condor air compressor pressure switch, 125/155 PSI. 240V, 4-Port manifold. Replace the pressure switch if the compressor no longer cuts in or out at the designated pressure (PSI), if the unit doesn't turn on or off,...

Old Part Numbers: 60-8-61-81/4" compression nut and sleeve. Order two, one for each end of the tube.

Air compressor pump gasket kit (dayleap). Includes head-valve plate, cylinder, crankcase, bearing case gaskets, and oil seal. Note: Gasket kit is for the DAYLEAP (metal) style.

Old Part Numbers: 4L540Air compressor v-belt, 54". Replace if frayed or slipping.Specifications A-type belt, 1/2" wide Outside Dimension: 54" "A" Belt Conversion: A52

Air compressor valve plate assembly. Poor performance or air leaks out of the intake filter while the unit is running? The valve plate assembly is probably the problem.

Old Part Numbers: PG0250300BTBottom-mount, 1/4" MPT, 300 PSI air compressor pressure gauge.Specifications NPT: 1/4" Dial / Face: 2" PSI: 300 PSI Bottom-Mount 

Old Part Numbers: 145-0488Part# change, order part# S145-0488.