These split and hinged optical tube mounting rings are made of cast-aluminum, feature quick release, hinged clamp knobs and felt lining. Designed for use with GSO mounts, they also fit with some other brands of mounts as well.
Inside diameter (ID) is listed. Choose the size that matches the outside diameter of your telescope tube.
176mm Tube Ring fits 153mm (6") telescope.
230mm Tube Ring fits 203mm (8") telescope.
303mm Tube Ring fits 254mm (10") telescope.
354mm Tube Ring fits 304mm (12") telescope.