comments:
I see these in my Amazon purchase history from around the time the time I posted that, so I assume these are what I was talking about. They are no longer available, but the listing should provide whatever info you were looking for. https://www.amazon.com/dp/B0BZ3BQYM7 The machine that my Ender 5 plus morphed into has 3 oldham couplings now, and my purchase history on Amazon only shows this 2 pack, so I know I got some from somewhere else at some point when I converted to Hydra. In general, I wouldn't overthink the purchasing decision when it comes to these. As long as the machining tolerances are decent, they will do the job well. The thing you need to check carefully before purchasing is that the hole spacing matches that of your lead screw nuts (it' is not the same for every printer).