Celestron 1.25" fit 20mm Erecting Eyepiece for Viewing terrestriallyCelestron 1.25" fit 20mm Erecting Eyepiece for Viewing terrestriallyCelestron Erecting Image Eyepiece Provides Corrected View For Newtonian Reflector. This Allow Newtonian Reflector Telescope To Be Able To Use For Terestial Viewing. 20mm Native Focal Length