Comfortable Eye Relief & Adjustable Eyecup: Generous 15mm eye relief with 9mm focal length allows comfortable viewing distance during astronomical; fold-down rubber eyecup design more fit the glasses wearer that prevent stray light entering when using; You now have another opportunity to obtain the renowned "Gold Line" eyepiece from Astromania Universal 1.25 inch Compatibility: Equipped with 1.25-inch (31.75mm) compatible with all standard 1.25" focusers of telescope; diagonal mirror ; barlow lens and other telescope accessories; Included standard 1.25” filter thread connect to telescope filter 66 Degree Ultra Wide Angle Eyepiece: Provide impressive optics with an enormously wide 66 degree apparent field of view (AFOV); Perfect for clearly observing planets or deep sky objects and offering expansive views of moon star clusters and Milky Way Advanced 6-Element HD Optics: Precision-engineered with muti-coating optical system are characterized by highly effective coatings and high light transmission, which delivers sharper and clearer observed images with better color correction and contrast Professional & Precise Detailed Design: All metal alumnium construction for long time use; Equipped with two dust-cover for better protecting eyepiece; blackened lens edges eliminate light scattering and minimize internal reflection with maximize contrast This high quality eyepiece features a 5-element design that offers superior sharpness. All air to glass surfaces have a multi-layer coating (so these are fully multi-coated, even though the barrel imprint may say "multi coated") for maximum light transmission. The long eye relief allows for a comfortable viewing distance. All lens edges are blackened for superior contrast. The insert tube is smooth-sided and is threaded for standard 1.25" astronomy filters. Ultra wide lens eyepieces offer a generous 66- degree apparent field of view, allowing more sky to be viewed at one time. They provide sharp image right across the field. The rubber eyecups are included for viewing comfort and to keep out extraneous light.