About this 3D model

This is a two piece bulkhead that can be used to pass a standard size aquarium airline through a thin walled vessel. I use it to pass airlines through the walls of algae reactors, but the same concept could be used for other tasks such as hydroponics. The fit for both the airline and locking ring should be quite tight, and ideally it should all hold together with just friction. If not, a little silicone spread over the airline and both parts of the bulkhead should keep things sealed up.