The first stage removes moisture and particulates down to 40 microns; features a pop-up indicator that alerts you to excessive flow or a plugged element. Second stage removes oil aerosols as small as .01 microns. Both 6-oz. metal bowls have sight glasses and manual drain valves. Regulator has a reinforced diaphragm for repeated accuracy, and a 0-160-psi gauge. Maximum 150 psi; maximum flow 25 cfm.