1 1/2" to 40 or 50 mm diameter (male spigot) ("Quoted In Internationally adopted B.S.P.T. British Standard Pipe Thread - Actual outside thread diameter is approx 1.882")For example - 1 1/2 (6/4") Plastic nut with rubber seal at one end for connection to items such as bath waste connection. Other end connected to 40 or 50 mm female *Pushfit / *Solvent / Compression connector.