' Compound Gauge, General Purpose, 4-1/2 In., 30 In. Hg Vac to 300 psi, Connection Size 1/4 In. NPT, Connection Location Lower, Smallest Graduation 1 Hg, 1 psi In., Accuracy +/-0.5 Percent, Case Material Cast Aluminum, Case Color Black, Socket Material Brass, Tube Material Bronze, Lens Material Glass, Operating Temp. Range -40 Degrees to 140 Degrees F, For Use With Non-Explosive Gas Or Liquid That Do Not Crystalize And Corrode Copper Alloy '