Celestron Omni 2X Barlow Lens Double the magnification of each eyepiece you own with the Omni 2X Barlow Lens Keep the eye relief of your eyepieces while getting 2X the power Slides into 1.25 focusers and diagonals and accepts 1.25 eyepieces Fully multi-coated optics with blackened edges for good light transmission and minimal reflections