573002A Caleffi Auto Fill Combo. 1/2" NPT Female Union Inlet, 1/2" FNPT Outlet. No Gauge.

Pre-adjustable automatic filling valve with dual check backflow preventer. Brass body. Max. inlet pressure: 175 psi. Max. working temperature: 150 °F. Setting pressure range: 3—60 psi. Preset outlet pressure: 15 psi.