FMC SVBONY telescope eyepiece with 4-elements in 3 groups and FMC film increase the transmission of lights; internally blackened eyepiece barrel to avoid internal reflection and provide a crisp image Long eye relief 20mm eyepiece has 17mm eye relief is ideal to make you not feel tired despite you viewing long time. Comfortable ultra-wide field that naturally more powerful to get bright and sharp viewing SVBONY 68-degree ultra-wide-angle 6mm eyepiece has a comfortable and wide field of view, suitable for planetary observation; the 68-degree ultra-wide-angle field of view allows for a broad view of the moon, star clusters, and the Milky Way. The observed image is brighter without introducing additional chromatic aberration, making the image clearer The 1.25-inch lens barrel is equipped with m26.5*0.6 standard internal thread, which can accommodate standard 1.25-inch filter lenses The eyepiece lens edges are treated with black to reduce the scattering of stray light and improve image contrast The lens barrel is internally threaded for diffusing and coated in matte black to reduce internal reflections and provide clear images