Hoffman Air Valve 401425 1B, 1/4" Adjustable Straight Convector Air Valve

Air Valve (non-vacuum)
Float-type vent
Adjustable port for true proportional venting €“6 port settings from slow (1) to fast (6)
Telescopic siphon tube
1„4" NPT straight shank
Maximum operating pressure 1.5 psig (0.1 bar)(Drop away pressure - maximum pressure against which the vent can open).
Maximum pressure 10 psig (0.7 bar)