Mid-West Instrument P/N 140-AA-02-OO 0-50 PSID, Model 140, 2.5" Dial, 0-50 PSID DP Range, Plastic Case, Aluminum Body, SS Trim, Buna-N Diaphragm Wetted Parts, 1/4"FNPT Top / Bottom Connections, 3000 PSIG Max. Working Pressure, 2% of FS Ascending Accuracy,