... vacuum degree,it is easy to use4 Intake valve adopts filter facilities avoid the reagent was polluted5Vacuum controller can supply for ... vacuum degree(gradient control needs to another software) Vacuum controller V-3000 with excellent controlthe vacuum deree.it can connect ... Methylene chloride,benzene, Trichloro ethane,and ethanal etc .Vacuum controller can replace the inert gas so that sample is not ...