Coronado 90 mm Doppel-Stack-Adapterring - AP190

This ring fit perfectly onto my SM90 etalon, and the machining is precise enough that I had zero issues with threading. The whole double stack setup came together smoothly, and the difference in contrast was immediately noticeable.

I was worried about alignment, but this ring fit perfectly onto my SM90 etalon with zero play. The machining is precise and the anodized finish matches the rest of the setup. Now I'm getting crisp double-stack views of the sun without any hassle.

Installing this adapter ring was surprisingly straightforward—the threaded connection felt precise and solid when I attached it. It seated perfectly with my external etalon, making the double stack setup much easier than I expected.