This thing is the gasket for the venturi assembly for many Sears/Kenmore water softeners (part #82 in the sketch). You can still get it from Sears Parts, but you have to buy the plastic venturi part with it. The kit costs almost $30 and in my experience, the only part you really need is this gasket. It shouldn't cost more than $.25. Even with the plastic venturi, the cost shouldn't be more than a couple of dollars.
Anyway, this is the kind of price gouging that makes me want to find a different solution. Before I got my 3D printer, I made one of these gaskets with a tire patch and xacto knife. It worked, and was very inexpensive, but was difficult to make accurately.
This is my 3D printed version. I used TPU because that's what I have. Ninjaflex or TPE should work as well.
Printer: FlashForge Creator pro
Rafts: No
Supports: No
Resolution: .1
Infill: 100%
Notes:
I recommend printing at 100% infill for maximum seal. My prototype was printed at 25% because that is my default and I forgot to change it. It still works just fine, but if/when I print another I will make it 100% infill.
The author marked this model as their own original creation. Imported from Thingiverse.