Valve, Zone, 2 Way Normally Closed, 3/4', Sweat, 24Vac,, 3/4" sweat two-way normally closed quick fit zone valve , hydronic control , 24v, spring return to close, brass body, stainless steel stem, brass seat, screwed terminal block , manual opener, 20 pound maximum closeoff pressure, normally open spst auxiliary switch, 3.5cv