A guide to Illinois Watch Co. size 12 watches, Grade 439.
Run.
Date
From
To
Total
H/O
Jls
Adj.
Named
1
1918
3,268,951
3,268,960
10
O
21
3 Pos.
Illinois Watch Co. Extra
2
1918
3,268,961
3,269,000
40
O
21
3 Pos.
Illinois Watch Co. Extra
3
1918
3,482,481
3,482,500
20
O
21
3 Pos.
Illinois Watch Co. Extra
4
1919
3,650,901
3,651,000
100
O
21
3 Pos
Illinois Watch Co. Extra
5
1920
3,761,951
3,762,000
50
O
21
3 Pos.
Illinois Watch Co. Extra
6
1921
3,904,851
3,905,000
150
O
21
3 Pos.
Illinois Watch Co. Extra
 
Total
370
 
 
Grade 439 runs.
Serial numbers used on this page by the kind permission of  
Russell W Snyder
Last update 12/24/2015.
Grade 439,
21 ruby and sapphire jewels adjusted to 3 positions, manufactured from 1918 to 1921 a total of 370 movements in 6 runs make up this grade. Model
1XT open faced; bridge movements of high quality with Illinois superior motor barrel, double roller and simple regulator.

Observations,
The movements have broad striped pattern and all named Illinois Watch Co. They have burnished set jewels on the bridges and silver snap on bezel
dials. This was the fourth of the Extra thin models to be made and came in solid gold and gold filled cases and were factory cased, Knapp, Solidarity
and Wadsworth were some of the case makers in 14 and 18K gold and gold filled with enamel trim, many of the watches were sold with private label
dials,

Description,
21 ruby and sapphire jewels; adjusted 3 positions, heat, cold and isochronism; has a specially quality tempered and hardened compensating balance;
double roller escapement; steel escape wheel; gold center wheel; Breguet hairspring; Illinois superior motor barrel; simple regulator adjustment; and
safety recoil click.
Image from the first run.