You need a 3/8" NPT thread filter/water separator for this 15-gallon air compressor.VEVOR
This model’s outlet port is 3/8" NPT, which is the standard thread size for most VEVOR air compressors in this class.
Choose a filter/separator with 3/8" NPT inlet/outlet and a max pressure rating ≥125 PSI (matching the compressor’s max pressure).
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