With many eyepiece designs, you usually have to sacrifice a sharp image at the edges of the field if you prefer a wide field of view. Or vice-versa, if you want tack sharp images at the edges, youd find the best images are those eyepieces with a somewhat narrow field of view. Well, now you can have your cake and eat it too! Introducing the Orion 15mm Ultra Flat Field Telescope Eyepiece. With a generous 65-deg apparent field of view, this eyepiece provides 25% more field of view than a typical Plossl, all the while providing a fantastic image from center to edge. The Ultra Flat telescope eyepieces are fully multi-coated to maximize light transmission to your eyes, as well as blackened at the lens edges to minimize light scatter internally and boost contrast. And with a generous 16mm of eye relief, youll be able to see that entire field of view, even while wearing eyeglasses. This 15mm Ultra Flat Field telescope eyepiece fits all 1. 25" focusers, or in a 2" focuser with a 2"-1. 25" adapter. It sports fold-down rubber eyeguards so you wont scratch your eyeglasses, and also to provide a comfortable feel when viewing through the eyepiece. The 1. 25" barrel is threaded to accept standard telescope filters, and comes with protective lens caps.