(Heavy Duty 1/4" Male NPT Hex Head Plug. These plugs are hollow and not solid. Heavy Duty 1/4" Male NPT HEX Plug. Make sure your application has 1/4" threads. These can be used with 1/4" Female NPT air tank ports and fittings.).
1/4” NPT Female to 3/8” NPT Male Brass Reducer Fitting Adapter For Gauge Sensor
4 1/4" NPT Male Brass Pipe Hex Plugs For Air Tanks, Air Ride Solenoid Valves
1/8-27 NPT Female to 1/2-14 NPT Male Gauge Sensor Thread Adapter Reducer
3/8" NPT Brass Barstock Street Tee Pipe Fitting 3/8" NPT Male X 3/8" Female NPT
Parker 3/8 NPT Brass Street Tee 3/8 NPT Male to 3/8 Female NPT VS2225P-6
4 3/8" NPT Brass Barstock Street Tee Pipe Fittings 3/8" NPT Male X 3/8" FNPT