Imperial Eastman Manifold Gauge Set 2-Valve Brass HVAC   Imperial HVAC Refrigeration Charger Manifold is a top-quality tool that is perfect for charging your refrigeration system. It comes with a range of features that include a red high side hose, blue low side hose, and yellow service hose. The gauge is designed for use with R-502, R-12, and R-22 refrigerants and has a vacuum unit measurement of PSI.