Baker Instruments AHNC Series Stainless Steel Dual Scale Pressure Gauge, 30 inHg-0 inVac Pressure, 2.5"Dial, +/-1.6% Accuracy, 1/4" NPT Back Mount, Glycerine Filled 2.5" diameter dial pressure gauge Dual scale (inHg/kPa), 1.6% accuracy Stainless steel housing and brass parts Back mount 1/4" male NPT connection Glycerine filled