The Off-Axis Guider have Large prism, it greatly increased the area of OAG prism guide star compatible with 183, 174 CCD cameras improved: up to 1500mm primary telescope for OAG guiding that can be faster at finding and Easy-Guider the area is the 6-7 times of the QHY5L-II-M guide camera Specification: Input: M48, M54, with 360 degree rotatable helical Output: M54, M48, M42, with 360 degree rotatable helical Guider Connection adapter: 1.25" helical focuser Thickness: 26mm
