Reducer Alan Gee Mark II is made for Schmidt Cassegrain telescopes from Celestron and Meade. It reduces the focal length and corrects the field of view, improving the focal ratio of a f/10 Schmidt Cassegrain to f/5.9. The exposure time is reduced to 35%. The field curvature is corrected, stars are sharp up to the edge of the field. Usable field of view up to 32mm diameter with very good correction and good illumination. The Alan Gee is suitable for all Schmidt Cassegrain telescopes from Celestron and Meade. It is not suitable for EHD and ACF telescopes. Supplied without connection adapter in robust plastic case.