Rude Star Finder and Identifier, US Navy, 2102-C, A-N Type 1

From the National Museum of American History:

This star finder, designed for aeronautical use, was based on the Rude form as modified by Elmer Collins of the United States Hydrographic Office. It consists of a white plastic planisphere with the northern sky on one side and the southern on the other that shows all the stars in the American and the British Air Almanacs; nine clear plastic altitude-azimuth templates for use at different latitudes up to 85° north and south; an instruction card; and a leatherette container. It was published in March 1942 under the authority of the Secretary of the Navy, and cost $2.50.

A cool WWII-era aviation navigation artifact indeed. The leatherette envelope has a couple of tears and is a bit delicate.  There are 10 clear plastic templates, a few are duplicate, so not represented here as complete. Also included is a white plastic navigation ruler FSSC 88-R-900.