Gosky 1.25" Moon Filter & 2X Barlow Kit for Telescope Eyepieces Moon filter and Barlow lens both essential accessories for telescope users. Moon filter helps to view the moon more clearly. 2x Barlow lens to double magnification. Works on Celestron, Orion , Sky-Watcher , Meade and most brands of telescope. Both the barlow and the filter are precisely CNC-machined.