The Rigel Quikfinder comes with two plastic bases (one for large and one for small telescopes). However, you can purchase additional bases for use on multiple telescopes. Leave the bases attached to the telescope tube, and simply unclip the Quikfinder from its base on one scope and move it to another telescope if you need to. Easy clip-on / clip-off means that there are no screws to fumble with.
This small base can be used on tubes up to about 6" in diameter.