The 3AL is an ideal alternative to rotary vane vacuum pumps and older liquid ring technology. The 3AL arrives ready to use and requires no external water or oil supply. It has a self- contained internal water circuit, is oil and maintenance free, and is insensitive to dust and water vapor. The only thing it discharges is cool, clean air. The 3AL has an operating range of 20-180 CFM and can achieve a vacuum pressure of 28.5"Hg (35 Torr ).