Two-stage 1⁄2-hp High-Vacuum Pumps produce 1-micron ultimate pressure. Rotary sliding vane operates quietly while providing free air displacement (85Lpm or 142Lpm). Gas ballast helps purge moisture from the vacuum system. Trap reduces the risk of oil being sucked back in. 3-cfm units have an oil capacity of 785cc (27 oz.). Pumps have an operating temperature of 30°–170°F. Intake port has a 3⁄8" O.D. for 3⁄8" I.D. tubing. 85L model is available with a Bourdon-type, steel-case gauge that checks vacuum at the intake. 2-1⁄2"-dia. dial; 0–30" Hg.