I just bought these a few days ago but decided to go with a different solution. These have not been mounted or used in any way. This is exactly what you need to mount an 80mm Finder or piggyback a refractor with tube size of 60mm-80mm on your SCT. Comes with dovetail mounting. They will also slide on the Losmandy Piggyback rail for SCTs. I paid $105.00 plus shipping. You can have these for $75.00 and I'll pay to ship FedEx 2nd day.