The McAlpine WC-BP1 is a plumbing connector designed to connect a 3½ inch (90mm) diameter outlet from a toilet bowl to a 4 inch (110mm) diameter soil pipe. This connector features an 'O' seal socket, which ensures a watertight seal to prevent leaks. It is suitable for use with 3"-4" (110mm) pipe and has a 3½"/90mm 'O' Seal Socket. The finned seal spigot is for internal connections to cast iron, plastic, or clay 4"/110mm pipe. It is designed for use with McAlpine Rigid or Flexible WC Connectors with a 4"/110mm rubber outlet seal. The WC rubber outlet seal is removed, and the plain end of the WC Connector is cut to length then inserted into the 'O' seal socket. This connector is ideal for low-level connections and includes a 1½" Universal Vent Boss with a supplied blanking cap. It is compatible with both PVC and cast iron pipes. Made from high-quality materials, it is designed for easy installation and use.