Orion 8923 20mm Expanse Telescope Eyepiece This 20mm Expanse 1.25" telescope eyepiece offers a wide field of view and superior optical performance at a bargain price Long 18mm eye relief lets eyeglass wearers view the entire field comfortably without removing their glasses Expanse eyepieces offer a wide 66 degrees apparent field of view to let you see more of the sky Delivers sharp views with good color correction and high contrast Aluminum barrel is internally blackened to eliminate internal light scattering, and is threaded to accept 1.25" Orion filters