Celestron LER Eyepiece for Regal M2 Versatile eyepiece can be used on Celestron spotting scopes, telescopes and other optical instruments that have a 1.25" eyepiece mount Extra-long eye relief of 32mm with removable rubber eyecup for use with eyeglasses or shooting glasses Larger viewing area allows user to quickly acquire and easily follow subjects as they move Waterproof and nitrogen purged for use in all weather conditions Celestron' s proprietary XLT coating increases light transmission through the optical path for brighter images and increased resolution