National boilers, radiators, and specialties: catalog no. 26 (1920)
National Radiator Company · National Radiator Company · leaf 66
It does notclose against water.List price, each . $2 80 The No. 5 Hoffman Quick Vent Float Air Valve is a perfect venting devicefor blast coils or vent stacks. It is open for air passage but closed tight againststeam or water.List price, each $8_0Q The No. 6 Hoffman Quick Vent Float Air and…
