Hamilton 4992B 24 Hour Navigation Master pocket watch c1970

This is a 16s 22J pocket watch made for the US Government at the later stage of Hamilton production when they were using up 4992B models made much earlier for later military work

Movement – the high quality nickel ¾ plate movement has a lever escapement and a micrometer regulator. The movement has a hacking feature, so that when you set the hands the balance stops allowing you to synchronise your watch with others. The movement has a wheel and extra jewel positioned on the top plate, this brings the jewel count from 21J to 22J. The movement is signed “Hamilton Watch Co, USA, 4992B, 22 Jewels, Adj Temp & 6 positions” # 4C142364 and is in 95% mint condition

Case – the movement comes in a keystone base metal open face case, which has a screw off back and front. The case is engraved on the back “Navigation Master Watch, Type AN-5740, H.W.Co, Part, No 33016, DAAA25-67-C0565, US” The case is in 95% mint condition – hardly any signs of use, which is unusual for a pocket watch

Dial – the black paint on metal dial has a set of white hands with sweep centre seconds hand. The dial has an inner chapter ring from 1-24 and the hands make on revolution every 24 instead of 2. The dial is signed “GCT” and is in 99% mint condition – very small marks

The watch has a synthetic glass

The watch measures 51mm wide x 15mm deep

The watch is stem wound / stem set