Course Line Indicator, Type 331A-1A; Collins Integrated Flight System FD-101/102
The Course Line Indicator, Collins Type 331A-1A, was a panel-mounted instrument for displaying the aircraft position with respect to the chosen course, according to the on-line Rockwell Collins Museum, and its brochure (see photos). It was intended to provide the pilot with "a clear and unmistakable picture of his position with respect to his chosen course."
The Collins Course Line Indicator is part of the 1950's-era Collins Integrated Flight System, combining Flight Director and Automatic Pilot systems used in civil aircraft such as the British ATL-98 Carvair (surplus Douglas DC-4's converted to carry passengers and vehicles) and Vickers Viscount (see cockpit photo), and possibly military aircraft of that era.
The Type 331A-A was likely used on the Collins FD-101 and/or FD-102 Integrated Flight Systems (FD-103's and thereafter used a smaller diameter display).
Measures approximately 10 inches long by 5 inches by 6 inches, and weighs ~6 lbs. The cover can be easily removed, revealing the gyro mechanism itself. It has a date stamp of July 1960, and is in fine cosmetic condition given its age. Makes a very cool display item.