The Sky-Watcher Esprit-100ED Professional Super APO Triplet Refractor OTA are instruments of the highest quality with optical performance rivalling or exceeding similar telescopes of even the most famous high-end telescope brands. The Esprit Super APO Triplets are designed for the most demanding astro-imagers, for use with the optional M48 Field Flattener (not included), but are also fine telescopes for visual observations. The premium, superbly-corrected optical systems deliver high-contrast images full of detail and zero detectable colour fringing, even on the brightest of objects. The 3-element, 100mm objective lens offers a focal length of 550mm with F-ratio of f/5.5. Accessories include: a 2"" Dielectric Star Diagonal, 9x50 Right-Angled Erect Image Finderscope, Tube Rings, 75mm Dovetail Mounting Plate and Heavy Duty Foam-Lined Storage/Transportation Case with Wheels.