Connect risers to the main, assuring proper division of water to each heating unit regardless of type and its position in the system|Recommended for most installations including cast iron non-ferrous base boards, free-standing radiation or convectors|Only one fitting is needed for most installations for adequate diversion for up feed radiation|For most applications, a second fitting can be used if higher resistance is required|Do not use for construction|Copper red ring monoflo fittings let you use a single pipe to serve as both supply and return main