Davis Instruments Mark 25 Master Beam Converger Sextant with Case and Manual

Description

Open Box. Uses 2 AAA batteries for light. Batteries not included.
The top of the line Davis plastic sextant, the Mark 25 features our Beam Converger™ mirror, sometimes referred to as a "full horizon mirror".
A special coating is applied to high quality optical glass to allow the user to see through this mirror, yet still pick up images as faint as low-light stars.
The Mark 25 is illuminated by a long-life LED and made of an upgraded plastic that is very stable.
Comes with instruction booklet.
I do not know anything about this item.  I do not know if it works or how it works.  I comes with everything you see in the photos.