NavList:

Paul,

These Hamiltons were used aboard WW2  and cold war aircraft. The 24 hour dial is unique and desireable for navigators. Price seems reasonable if all original. Notice the fine fast slow adjustment screw over the balance wheel. With patience using the Audacity app this watch should be adjustable to better than 5 seconds per day if kept at constant temperature.

Greg Rudzinski

From: Paul Hirose
Date: 2018 Jun 13, 22:05 -0700

While browsing a site which sells vintage watches I came across a
Hamilton 4992B. It has a 24 hour inner dial marked "GCT" and 60 minute
outer dial with sweep second hand. This is a 16 size watch, meaning the
diameter of the movement plate beneath the dial is about 43 mm. The 22
jewel movement is freshly overhauled. Price $525.00.

http://www.northernpartners.com/hamilton.htm
(near the top of the page)