2" Diagonal: Celestron #93519, made in Japan, see pic at Astronomics where it sells for $154 not including shipping. Standard ring attachment for Celestrons and Meades 8 through 14 inches. DOES NOT REQUIRE VISUAL BACK (the ring design should not be confused with non-ring competitors that cost less because they require a $25 visual back in order to attach to the sct). This part has never been used. Came with my C14, but didn't need it because I got an AP Maxbright. Original box and 2 caps.
The only part of this unit that I did use was the 1.25" adapter which walked away at a star party. I am including the Televue captive thumbscrew adapter as an equivalent substitute.