CARBO Instruments 2- 1/2" Pressure Gauge, Chrome Plated Steel Case, Dry, Vacuum Compound Gauge -30 InHg - 0 - 15 PSI, Lower Mount 1/4" NPT, Water, Air, Compressor, Hydraulics, HVAC, Gaseous & Liquid Media That Are Not Highly Viscous Or Crystallizing And Not Corrosive Or Oxidizing To Copper Alloy Parts