PRO-FLEX 1/2-in CSST Brass Hex Test Gauge in the CSST Pipe, Fittings & Accessories department at Lowes.com
3-1/2" Gas Pipe Pressure Test Gauge (3/4" and 1" pipe)
Leak Detection Gauge #17808 | WineKeeper
Ashcroft® Model 1082 and 1084 Pressure Test Gauges from Cole-Parmer France
Amazon.com: in-Line Water Pressure Test Gauge Kit for Plumbing Lines, Boilers, Water Tanks, Faucets - Home Water Pressure Tester : Industrial & Scientific