This is a 12mm corrugated conduit connector.
I scratched it while testing because I needed to connect a gap in the conduit. I couldn't find a drawing for this anywhere, so I had to design it myself.

1. First, I slide both conduit ends together as close as possible.
2. Then, I place this part over the connection and simply snap it shut.

This way, my conduit is protected and looks aesthetically pleasing.

I am sharing the STL files for both 12mm and 8mm conduit clamps so others can use them too.