Our vacuum package cover more than 1 mbara vacuum load to enhance your proecss requirements. When a gas compression task involves an overall compression ratio that cannot be economically reached by one ejector stage, two or more stages may be connected in series to accomplish that task. The load and the motive gases from the first stage combine to form the load into the second stage. The second stage may discharge into a third stage, and so on, until the mixture pressure is high enough to discharge into the atmosphere. Usually condensers are located between some of the stages to condense. out much of the motive steam and the condensable portion of the load vapors.