The VO-1000 was produced from 1939 to 1946 evolving through three distinct phases.
VO, 8 cyl.
Example - Phase I
Photo Credit: R. Bee, Collection of Mark Laundry
W.Duluth, MN. Aug. 11, 1978
US Steel 907
Former Oliver Iron Mining with custom order, longer frame
Example - Phase II
Baldwin Photo - collection of LeClaireRail.com
Litchfield & Madison 100
Existing Example - Phase III
Photos by: Ed Horm
B&O Museum, Baltimore, MD - Spring 2005