Applications Used for hydraulic and pneumatic systems Compressors, compressed air system Suitable for fluid medium which does not clog connection port or brass Special use for stable and long life. Case:black steel Ring:black steel Window:acrylic Socket & connection:brass Movement:brass Bourdon tube:copper alloy Pointer and dial:aluminum Range:vacuum, compound 0 to 6000 psi Class:1.6% Mounting type:bottom