We had two different ones in the factory. One was an electronic auto drain on the tank, noisey as crap, but got all the moisture needed for running air tools. The other set up was on a robotic machine and we used some of the air to cool the circuit board boxes. It had to be 100% moisture free, and when it wasn't, wow did weird things happen there, lol! It was a refrigerant drier, not cheap but worked incredibly awesome. I built one off a couple pictures of a fellow on Miller Welding's forum, think his name is pile buck, out of copper tubing and a big garbage can, works great until the cooling water freezes in the garbage can when the furnace went out, then took a little fixing but that is not the driers fault.