This extra Telrad base is for those who have more than one telescope, and who want to transfer their Telrad finder from scope to scope to save the expense of buying a second Telrad. It comes with double-faced tape for mounting to metal tubes, plus screw holes should you want to attach it to a Sonotube Dobsonian or equatorial mount optical tube. The two plastic locking thumbscrews make removing and attaching a Telrad to the already -installed base a matter of moments. The dovetail bracket positions the Telrad accurately and repeatably each time the finder is installed, making recollimation rarely necessary.