Boiler feed water pressure regulator, 1/2 inch female pipe thread inlet andoutlet with 1/2 inch female pipe thread bottom connection for installation ofexpansion tank, fills the boiler & system piping with water & maintain waterpressure, provides make up water to the system in the event of system leaks,fast fill feature speeds filling & purging of air from the piping on theinitial fill, manual purge lever included, stainless steel strainer protectsvalve disc from fouling, tight seating check feature. Easy installation and easy handling.