I'm trying to source my pool equipment o-rings by trade sizes and material.
I've figured out all the trade sizes; but does anyone know the material?

Buna? Viton? Nitrile? Silicone? Butyl?
Does it matter?

If nobody knows, I'm going to go with Viton; but it would be better to
know for sure what the OEM material is for pool pump o-rings.