For Measuring Pressure Of Fuel, Oil, Water, Air Compressor, Hydraulics, HVAC, Coolant, Gaseous & Liquid Media Pressure That Are Not Highly Viscous Or Crystallizing And Not Corrosive Or Oxidizing To Copper Alloy Parts 1.5 Dial Size, 1/8 NPT Connection Brass Chrome Plated Stainless Steel Case, Burdon Tube Type Brass And Copper Alloy Wetted Parts, Polycarbonate Window Lens, Glycerin Filed Keep Needle Steady During Engine Vibration Easy To Cut/Vent Plug For Accurate Readings, Single Scale Pressure Range PSI ASME B40.1 Grade B Accuracy Compliance ± 3-2-3 % Of Span