Manufacturer: Brunton F-BOSS50M
By moving the hinge for the sighting mirror to the center of the base plate, users are now able to sight objects faster and more accurately along the same direction of travel mark used for map navigation. We've also added a meridian insert, so that you still have Brunton's patented tool free declination system, but the meridian lines stay down on the map for greater ease and more precise headings.
Specifications and Features:
BRUNTON O.S.S. alignment system
Tool free declination adjustment
On the map Meridian lines
2 degree resolution
Mid-hinged sighting mirror
Weight: 2.2 oz.
Limited Lifetime warranty
Made in the USA