GS,
Be cautious when buying. Lots of folks are/were getting ripped off on Ebay and other places buying Yong Heng's. Some didn't get a compressor at all, others are getting cheaper knock offs, ( I laugh a little saying cheap knock off when it comes to chinese products
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Yong Heng makes 3 different models, You want the "hard back" version. This will include a first stage cyclone water/oil separator and a second stage water/oil separator. It also comes with a final, tampon type filter. This final filter is NOT enough to insure clean, DRY air. So, I'd also recommend buying/building a High pressure molecular sieve filter to remove ALL the moisture and other bad constituents from the air before it enters your tanks/air tubes and causes corrosion. I'd not use the recommended AW46 oil, use a good quality, synthetic oil for HPA compressors. It's EXPENSIVE, but,worth it I think in helping to avoid the compressor launching it's head.... in other words BOOM!
Good luck and do lots of reading before you fire up that new compressor, as you probably well know, HPA is nothing to mess with.