Celestron - Micro Guide Eyepiece 1-1/4 inch

This multi-function guiding eyepiece features a laser-etched reticle with a built-in battery
illuminator. The eyepiece is a multicoated 12.5mm Abbe (4-element) Orthoscopic. 
Usage
possibilities include: direct guiding on stars outside the center of the field of view; greatly
improved off-axis guiding to capture much fainter, sharply focused guide stars without reducing
limiting magnitude; and measuring position angles and separation of double stars. 
The
Micro Guide Eyepiece is totally free of internal reflections and offers sufficient eye relief for
the reticle to be viewed easily, even with eyeglasses. Its finely etched micrometer scale has
gradations 50 microns apart and 15 microns wide. Included are: the eyepiece, built-in cordless
illuminator with adjustable brightness control, batteries and instructions. The apparent field of
view is 42°.