This 2" visual back threads onto the rear cell of 10" to 14" Celestron SCTs with 3.25" male threads on the telescope's rear cell. It provides a full 2" unobstructed opening (unlike most visual backs). Use with 2" accessories that slip in, i.e. 2" diagonal, Barlow, 2" eyepiece or binocular viewer. It features our unique brass locking ring design and 3 large thumbscrews to hold your accessories securely and squarely; ideal for critical applications. If you prefer to use just one thumbscrew on occasion (perhaps if you are interchanging accessories frequently), simply remove the extra 2 thumbscrews for that session.
Please verify that your instrument has a 3.25" male thread on the rear cell before ordering.
Important Note: Celestron Edge HD scopes have a restricted rear cell that may not allow accessories with a long nosepiece to fully seat in this adapter. Ffor instance, the AP Maxbright diagonal will not seat. It is recommended to choose the ADASCTLC27 and ADA2003A or ADA20132 as an alternative when using the Edge HD scopes.
This adapter has a net spacing distance of 1.5" (38.1 mm).
It has a safe nosepiece insertion depth of 1.1" (27.9 mm).