J-KEM DVR-200-EV Digital Vacuum RegulatorJ KEM DVR 200 EV Digital Vacuum Regulator The DVR 200 EV has the same stainless steel pressure transducer inside, but the vacuum valve is outside of the controller. The value of this design is that the vacuum valve can be cleaned or replaced much easier than the valve in the classic DVR 200. Some applications, like distillations or stripping large volumes of solvent, can leave residues inside the valve which causes it to fail. Replacing the vacuum