Celestron 90 Angle Diagonal Mirror 2" with XLT Coating for Schmidt-Cassegrain Telescopes Reviews:
Celestron 90d 2" diagonal mirror
Excellent diagonal for an SCT scope. Connects directly to rear cell using SCT threads. Eyepiece side comes with 2" - 1.25" adapter. Both sizes have compression ring clamps. Glad I bought it for my Nexstar 6SE.