Dental amalgam is one of those odd products still produced at scale in production cabinets, rather than larger engines. Such is the way of the medical industry, I suppose, slow to adapt to change. 

Still, I was contracted to create a cabinet design for producing the stuff. I made it cheap and efficient, using just two neat chambers of size 5. Only afterwards did they tell me they had a cabinet for me to use already. So I tweaked my solution to fit within their premade cabinet, including the pesky extra conduits.

To whoever deigned to use this cabinet for dental amalgam before me: I hope you see the light and stop using irregular chambers for your cabinets. :)