Hey all: Where is your "go to" source for high pressure (e.g. 5000 psi) air fittings? I'm trying to source parts for a bottle conversion (e.g. hex nipple NPT 1/8" and such) and want to get the proper pressure rated parts. Is it a spec or ASTM rating I should look for? I ordered a 316 stainless hex nipple off of ebay that stated rated for high pressure (with no PSI rating). I plan to experiment with a regulated ninja tank attached to my Prod guage port, but I would want that to be at least 3000psi rated. Thanks in advance.