See the whole picture with Ultima Edge. These flat-field eyepieces were designed to provide an ultra-sharp, ultra-clear, crisp image from the center all the way to the edge of the field of view. The 10mm Ultima Edgeeyepiece features fully multi-coated optics and a 5-element lens design, maximizing light transmission. The Ultima Edge10mm has a generous 60 field of view, perfect for viewing planets, stars and the Moon's surface. This eyepiece provides high power magnification, perfect for those times when you want to get up close to smaller objects. Body The 10mm Ultima Edgeeyepiece's main housing is machined from high grade aluminum with a black anodized outer surface. Its 1.25" mounting barrel is internally threaded to accept threaded to accept standard 1.25" filters and adapters. It is compatible with 1.25" star diagonals and focusers. On the exterior of the eyepiece, you will find a uniquely designed, molded rubber grip ring for non-slip handling during observing sessions, even if you have gloves on. Viewing through the 10mm Ultima Edgeeyepiece is comfortable for both eyeglass wearers and non-eyeglass wearers alike, thanks to the fold-down rubber eyecups and long eye relief of 16mm. Convenient Parfocal Design Spend more time observing and less time focusing! When you buy more than one Ultima Edgeeyepiece, you can switch between them without refocusing thanks to theirparfocaldesign. With a set of Ultima Edgeeyepieces in your kit, you'll be able to enjoy a wide range of high and low power views--and switch between them quickly and easily. That means you can get more out of every observing session. NOTE: Ultima Edge24mm is not a parfocal eyepiece. Ultima Edgeeyepieces are only parfocal within the line and do not maintain focus when swapped with parfocal eyepieces from other brands or series.