Adapter ring to convert the thread on the rear cell of many Maksutov-Cassegrain telescopes (including some of those made by Celestron, Orion, Sky-Watcher and others) to an SCT (Schmidt-Cassegrain) thread. Allows you to use SCT threaded diagonals, visual backs, focal reducers and other accessories on your Mak-Cass telescope. Has female Maksutov-Cassegrain threads on the inside all the way through and male SCT threads on the outside at one end. Precision machined from aluminum and black anodized.
Please note that the focusing knob on some Mak telescopes is quite close to the rear cell and there is a possibility that a 2" accessory coupled with this adapter may not screw on to your scope since the focus knob gets in the way. Please measure the separation between the focus knob and the 2" accessory you plan to use to ensure that you will be able to use SCT accessories on your Mak using this adapter.
* Weight = 0.4oz
* Total length = 12.6mm (0.49")
* Maksutov thread = M44.5 x 1.0 Female
* SCT thread - 2" x 24TPI Male
Note also that this adapter will NOT work with the Celestron NexStar, C-90, C-130 and Meade ETX series of telescopes since those do not use a standard Mak 44.5mm thread. Many of these other scopes use a smaller 35mm thread. So please make sure you measure your scope's thread diameter before purchasing this adapter to make sure it will fit.