First one died 20 seconds after starting. Second sent back due to internal "Lint" covering 1/3 of lens. What was not in the book or of customer service knowledge was that the lint was simply the track of lights the unit could not handle, like Venus, Jupiter, and street/country security lights. Shut it off for about 10 minutes and the lens is ready again. I wear glasses and the single focus on this unit does not come quite up to a sharp focus. It is good enough for hunting but just barely. The 12 degree field of view is well below other units sold by Optics Planet and there is no brightness control as on other units. I kept mine because it still does the job and it fits on the front of my scope.
Pros: Goes on front of traditional scope
Cons: Too small a field of view and needs a little more focus range
This review was written in the old system and had content requirements that are different than reviews written today.