A guide to Illinois Watch Co. size 12 watches, Grade 438.
Run.
Date
From
To
Total
H/O
Jls
Adj.
Named
1
1918
3,269,901
3,269,960
60
O
21
3 Pos.
Illinois Watch Co.
2
1918
3,269,961
3,270,000
40
O
21
3 Pos.
Illinois Watch Co.
3
1918
3,388,371
3,388,380
10
O
21
3 Pos.
Illinois Watch Co.
4
1919
3,482,401
3,482,480
80
O
21
3 Pos
Illinois Watch Co.
5
1920
3,650,601
3,650,900
300
O
21
3 Pos.
Illinois Watch Co.
6
1920
3,761,801
3,761,950
150
O
21
3 Pos
Illinois Watch Co.
7
1921
3,904,401
3,904,850
450
O
21
3 Pos.
Illinois Watch Co.
 
Total
1,090
 
 
Grade 438 runs.
Serial numbers used on this page by the kind permission of
Russell W Snyder
Last update 12/24/2015.
Grade 438,
21 ruby and sapphire jewels adjusted to 3 positions, manufactured from 1918 to 1921 a total of 1,090 movements in 7 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 brushed nickel pattern named Illinois Watch Co. They have burnished set jewels on the bridges and silver snap on bezel dials;
Knapp, Solidarity and Wadsworth were among the case makers. This was the third of the Extra thin models to be made and came in solid gold and
gold filled cases some with enamel trim, with many sold with private label dials and were factory cased.

Description,
21 ruby and sapphire jewels of extra quality; adjusted to 3 positions, temperature and isochronism; has specially tempered and hardened
compensating balance;double roller escapement; steel escape wheel; gold center wheel; Breguet hairspring; simple regulator; Illinois superior motor
barrel and safety recoil click,
Image from last run.