Aircraft Radio Corporation
Course Indicator ID-453/ARN-30 UH-1, OV-1, SAAMA, Kelly USAF Base
This is a Course Deviation Indicator type ID-453/ARN-30 as used in the Vietnam War era UH-1 Bell Huey Helicopter, OV-1 Mohawk, and C-7A Caribou. See diagram from the UH-1 Flight Manual. Measures 3.25 in diameter and ~7in deep.