iflysky: They are 304 stainless Tee and a close nipple I plugged the original gauge opening with a stainless plug, they are 1/8 inch threading. (see image) Each of the ports have a delrin seal disk but I also wrap the threads a couple times with Oatey fast tape thread sealer. I purchased my stainless fittings locally at a supply house here, just call around in your area some one will probly have them just make sure they are stainless steel to be able to handle the high pressure. I removed the silica from the original plexi tube that come with the compressor and placed one filter disk in the bottom of tube and one on top with the 13x molecular sieve in between. (there is no need to replace the exisiting internal tube). I purchased the sieve from
www.shopbvv.com For Oil I use Royal Purple synt 100 I have not used Coltri or Bauer oil so I cant give any info on those, but the Royal purple works very well in this compressor. You can fill your air guns directly and yes you just open the air drain after shutoff to release line pressure. For my air tanks I bought new it was worth the money and I know I have 15 years on them atleast and a hydro renew each 5 years is only about 40 bucks so I think a new tank is worth the money, I have not heard anything bad from the refirbished tank so it would be a personel preference on your end to make this consideration. I have 74Cuft and 2 100 Cuft either is a good setup I use my 74 in the field and the 100s in the shop.
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