Safety Traffic Light Manufacturing
From HighwayWiki
STLM Co. was incorporated in Milwaukee with a capital stock of $100k and a goal of making "automatic traffic directing posts."
Incorporated By: South Side Malleable Casting Co. (Walter W. Lange) Crucible Steel Casting Co. (Walter W. Lange) J.S. Lawrie (1614 Grand Ave.) John C. Warner
The Iron Trade Review, April 22, 1922