Forum » L40 pump - what size fitting is outlet

Hi This may seem a stupid question but I wish to attache some pvc pipework to the L40 pump. I need to know what size fitting will screw into the outlet on top of the pulp. Looking at this site it says 16mm int diameter, but measuring an actual L40 pump is looks like its a 1inch threaded fitting I would need. Can you confirm what size this threaded outlet is please? thanks