Orion 52067 Mak-Cass Adapter Ring for Schmidt-Cass Accessories Adapter ring lets you use popular Schmidt-Cassegrain accessories with Orion Maksutov-Cassegrain telescopes Compatible with thread-on Schmidt-Cassegrain accessories such as visual backs, 2" SCT diagonals, camera adapters, and more Now you can use 2" eyepieces or other SCT-format astronomy accessories with your Orion Maksutov-Cassegrain Adapter ring designed with an extremely low profile to maintain the full focusing range of the telescope Precision machined from aluminum and black anodized