OPTICAL TUBBE ASSEMBLY ONLY, DOES NOT INCLUDE THE BASE The 250P 10" Traditional Dobsonian Optical Tube Assembly from Sky-Watcher uses a parabolic primary mirror design, constructed of borosilicate, then polished and coated with Sky-Watcher's proprietary Radiant Aluminum Quartz (RAQ), producing a remarkable 94% reflectivity. With a 10" aperture, this Traditional Dobsonian OTA is 1235 times brighter than the human eye. This simple, yet effective, design is perfect for visual observation of faint objects, such as nebulae, star clusters, and galaxies. The telescope can support both 1.25" accessories as well as the heavier 2" eyepieces, allowing you to use virtually any eyepiece on the market. It includes two 1.25" eyepieces, a 1.25" adapter, a 2" eyepiece adapter, dust caps, and a 9x50 finder scope.