Calpha EV-series industrial grade dual-stage vacuum pumps are designed for reliable long time continuous operation. They have a balance between low cost and high performance. They come with gas ballast, which is designed to allow purposefully pull a less deep and slower vacuum by opening the gas ballast, allowing dry air to go directly into the pump and diluting the vacuum pull, and it also helps keep moisture, solvent, and other contaminants from getting stuck in the pump, and instead passing through to the exhaust. The built-in check valve prevents pump oil back flow.
It is important to note that pumps should always be ran in a well ventilated area. Light weight, low cost, compact design, low noise. Check valve to prevent oil back-flow.Gas ballast design, for better compatibility with moisture and solvent vapor. Different options for vacuum connectors (KF25, hose barb, etc).