Radio Magnetic Indicator ID-250/ARN

This Cold War / Vietnam War era Radio Magnetic Indicator (RMI) ID 250/ARN was made by Bendix for use in aircraft of the US military in the 1950/60's and used in the AN/ARN-14 Radio Navigational System (see illustrations).  This indicator was commonly used in US Army helicopters such as the UH-1 Bell Huey and the AH-1 Cobra, not to mention the B-52 Stratofortress Bomber (see image of flight panel) and the F-100 Super Sabre jet fighter (see image from flight manual).  

This indicator is in very good condition. The glass and case are intact and the lettering is precise and distinct. Measures 3.25 inches diameter and ~7 inches long.