The No. 67 Auto-Vent is a hot water float vent for use on convector radiators, baseboard radiation, and radiant panels. 1/8" auto float vent, up to 50 lb. pressure. 1/8" I.P. Male connection, 3-3/4" x 9/16". These are designed to be used in space that is limited and can be installed in trouble spots previously neglected or improperly vented. Vertical mounting. Bright brass finish.