Note: To prevent batteries accidently draining, they may be loaded by the manufacturer backwards into the light source (this won't harm the eyepiece). The batteries should visibly show the writing on the batteries when loaded into the end with the knob on it.
The battery type is AG20 or L1131C.
A 1.25 inch 12.5mm Illuminated Reticle Plossl Eyepiece. Anti-reflection fully multi-coated optics ensure bright and clear high-images at any magnification, with true color rendition.