[6170]71FL Series 80 Basic OTA Set Part # 6170 Description 71FL Series 80 Basic OTA Set Aperture 71mm Fluorite Focal length 400mm F-ratio 5.6 Lens configuration 2 elements in 2 groups Coating Fully-multi-coated Physical length 350mm Tube diameter 80mm Weight 1.2kg Filter 72mm (front hood) Parts included 2572, 7151, 77491, 7790 & 7835 Notes Needs a 2-inch holder for visual use