Celestron Luminos 7mm Eyepiece offers a wide 82º field of view in both high power and low power models allowing you to make the most of your telescope whether you own a short fast refractor or a Celestron EdgeHD telescope. Effortless The optical set is fully multi-coated for crisp sharp views. The Luminos eyepiece is parfocal which means you can switch out eyepieces during observing sessions with little or no additional focusing required. Construction The Luminos eyepiece body is made of polished and anodized aluminum. The insert barrel is threaded to accept filters this is a nice feature because you can change eyepieces without removing and reattaching the filter each time. Features A rubber grip runs around the equator of the eyepiece giving you a secure grip and an easy method for raising and lowering the retractable eyecup. Simply twist the rubber grip to adjust the height of the eyecup. The rubber grip also aids in keeping the eyepiece securely in your hands even when it’s cold or you have gloves on.