Very Simple RV Sewer hose coupler if you want to repair things Like me. The hose goes around the outside of it. It is aprox 73 mm on the outside This fit snug, and I did heat the hose a bit with a heat gun to stretch it over easily. I would Strongly suggest using RTV or silicone on the connector before you clamp or ziptie it so make sure there are no leaks.

V1 is super simpler but works, V2 I designed with a flange in the middle