Physical description

A World War 2 era W. W. Boes and Co. MKll astro compass typically used as an aviation navigation aid. It is manufactured from aluminum with black enamel finish.
An astro compass is a navigational tool used to determine true north from the position of the sun or astronomical bodies.

These are used in circumstances where magnetic compasses and gyrocompasses are unreliable, for example in the presence of magnetic field anomalies (such as polar regions, ships hulls, aircraft hulls, etc.).

Inscriptions & markings

Nameplate on the base reads "ASTRO-COMPASS MK II / The W.W. BOES CO. / DAYTON, OHIO, USA"