The Ralston DV0V-0000 23 inHg Vacuum Cylinder Hand Pump with 1/4" Male NPT Process Connection is a lightweight, compact pump that generates 23 inHg (584mm Hg) vacuum with ease. It is equipped with a large volume fine adjustment piston, which provides precise control, even at very low vacuums. The modular design makes field maintenance quick and easy. The pump precisely vents pressure with a soft seated bleed valve. Two outlet ports provide connections for both pressure reference and for device under test, thus eliminating the need for a tee. A low volume Quick-test hose and process connection can be attached to the pump without thread sealant or a wrench. The rugged, all metal construction reduces pressure changes due to temperature fluctuations.