SVBONY 1.25" 90 Degree Diagonal Adapter Erect Image Zenith Mirror Prism Fully Metal for Refracting Telescope Eyepiece Lens Standard 1.25'' diameter; fit for 1.25'' eyepiece and telescope focuser Work with refractor and catadioptric telescopes;not for reflector telescope Wide 90 degree angle;you can view correct image from refractor telescope stand and just look down with a comfortable angle Super easy to use;just insert into 1.25'' telescope at the silver end;the other end fix 1.25'' eyepiece by the screw Body material is full metal;optical glass lens provide clear and sharp image  With dust cover always keep your lens clear prolong life