Compound Gauge,Oxygen Service Cleaned,2-1/2 In.,30 In. Hg Vac to 30 psi,Connection Size 1/4 In. NPT,Connection Location Lower,Smallest Graduation 1 In. Hg, 1 psi,Graduations 10 In. Hg to 5 psi,Accuracy +/-1 Percent,Case Material Stainless Steel,Case Color Silver,Socket Material 316 Stainless Steel,Tube Material 316 Stainless Steel,Lens Material Polycarbonate,Ring Material Stainless Steel,Operating Temp. Range -40 Degrees to 150 Degrees F,Characteristics PLUS Performance