With a wide 68 degree apparent field of view the ultima duo 10mm eyepiece from celestron has multi coated optics to increase light transmission and contrast and 8 lens elements in 5 groups to guarantee the best chromatic aberration and field curvature correction it combines excellent optics with a built in t adapter for astroimaging and will fit both 125 and 2 focusers so you can use it with almost any telescope simply remove the rubber eyeguard to expose the t threads and attach your d