The Baader 2" Maxbright Diagonal can be attached to your SCT telescope in a semi-permanent fashion. However, attaching the diagonal directly on to the SCT rear 2" 24 TPI male thread is bound to result in an odd and inconvenient orientation of the diagonal for virtually all telescopes when the diagonal is fully screwed on. However, this problem can easily be solved with the use of Baader SCT Lock Ring.