2" 4-in-1 Adapter, Combo of 2" clamp with 4 focuser adaptations
Four in One 2-Inch Eyepiece Holder Clamp, M68
2" Four-in-One Adapter - combo of 2" clamp with four focuser adaptations;
M68 (Zeiss/Baader) / 2.7" (Astro Physics) / M60 (Synta Newtonians and Vixen) / M56 (Synta refractors)
On the telescope side it's got M60 and M68 male threads and M56 female thread, whilst on the eyepiece side it also has an M68 male thread (latter covered by a metal ring).