Astro-Tech 124mm Tube Rings

These split and hinged optical tube mounting rings are made of solid aluminum, anodized black for long life. They are felt-lined and have a large hand-tighten knob to lock them on your optical tube. A heavy nylon washer prevents the knob from marring the anodized finish. The rings have a 124mm internal diameter to fit refractors with a 124mm OD tube, such as the Astro-Tech AT111ED. The rings weigh 15.2 oz. each.

There are five 1/4"-20 mounting holes on the bottom of each ring for mounting the rings on an equatorial mount dovetail plate (not supplied). One hole is centered in the flat mounting boss in the bottom of each ring. It is flanked by a pair of holes on 60mm centers, and a second wider pair on 80mm centers. An identical set of five holes on the top of each ring allow installing a second dovetail plate to carry accessories.

Two 7/8" long x 1/4"-20 thread hex head bolts are supplied with each ring for mounting the ring on a dovetail plate or equatorial mount using the center hole or two flanking holes.