There are a pair of 5/16" posts threaded into the intake between the center and rear carbs. Hoses attach to this fitting. The fitting points to the passenger side. Another 5/16" hose runs to the PCV valve in the valley pan. The original "F" fittings were plastic. Heat and age have taken their toll and most originals are long gone. This piece is metal, painted cream color to appear as the originals.