These high-quality cast aluminum Sky-Watcher telescope tube rings are specially manufactured for us for use on our AZ3, EQ1, EQ2, EQ3-2, EQ5, HEQ5, EQ6, AZ-EQ5 and 6 as well as EQ8 mounts. They are available in diameters of 90mm, 102mm, 120mm, 130mm, 140mm, 182mm, 236mm and 285mm. They are hinged and lined with felt for easy installation of your telescope. After loosening the knurled screws, the telescope can be easily balanced and rotated. Scope of delivery: 1 pair of pipe clamps 90mm diameter! Power supply and batteries are not included!