One-and-a-half inch BSP joining nipple (approx 47mm outer diameter). Used in conjunction with gaskets to join sectional cast iron radiators together.
Right hand (normal) thread on one half and left hand (reverse) thread the other side. When the nipple is turned, the two radiator sections are brought together, compressing the gasket and forming a watertight seal.
1.5" BSP is the correct size for many of Castrads cast iron radiators including Queen, Rococo, Princess and Baron ranges. Not compatible with King or Grace ranges.