Coronado 40 mm Double Stack Adapter Ring - AP185

Name: Coronado 40 mm Double Stack Adapter Ring - AP185
Brand: Coronado
SKU: CORO-AP185
Price: 12.79 USD
Availability: InStock
Rating: 4.6 (5 reviews)

Coronado 40 mm Double Stack Adapter Ring - AP185 - Main image

$12.79 ~~$19.99~~ In stock

Category: Telescope Accessories

Coronado 40 mm Double Stack Adapter Ring

This 40 mm Double stack Adapter Ring is designed by Coronado and essential to double stack on an external primary Etalon for SM40.

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Customer Reviews (4.6 / 5 · 5 reviews)

Elizabeth B. ★★★★★ Oct 21, 2026

The alignment pins line up perfectly with the SM40 etalon, making installation quick and frustration-free. I’m seeing noticeably sharper contrast on the solar surface with the double stack setup now complete.

Abigail ★★★★★ Oct 20, 2026

Fits onto the external etalon without any wobble, which was my main worry with an adapter this size. The machining is clean and the threads are smooth, so stacking took me about five minutes total. Exactly what I needed to get the double stack setup working.

Daniel H. ★★★★★ Oct 18, 2026

Finally got it installed and the double stack alignment was much smoother than I expected — the threads on this ring are really precise. It snugged right onto the SM40 without any wobble.