Round Boiler Gauge Boiler Gauge Nominal Size 3 in Gauge Connection Location Center Back Gauge Connection Type MNPT Gauge Connection Size 1/2 in 0 to 100 psi Gauge Accuracy +/-3-2-3 Percent Basic Gauge Case Material Steel Basic Gauge Wetted Parts Copper Basic Gauge Lens Material Plastic 80 Degrees to 320 Degrees Boiler Gauge Temp Range - F Temp Range (C) 20 Degrees to 160 Degrees Case Material Steel Case Color Silver Socket Material Copper Alloy Tube Material Copper Alloy