Attach this adapter to any camera tripod that has a 1/4"-20 threaded post to add micro-motion altitude and azimuth control. Very useful for tracking celestial objects with binoculars or spotting scopes. I bought with the intent to use as a mount for a guidescope. Not well suited to that, but it has been good for tracking with my ST-80 on a tripod, or using with my piggy back adapter to do 35mm photography. I used this adapter to position and frame with the camera while keeping the scope centered on a bright guide star. Worked well, but my wife just got me an expensive Bogen Ball head for our anniversary, and my ST-80 is "permanently" attached to my C8 as a guide scope, so I just don't use it anymore. Got to sell it to buy more toys! Asking $25. Sells new for $32.95.