Like most steam loco builders, Baldwin experimented with diesel engines through the 1920s and early 30s. In 1939, the first of the new model VO-1000 (so named as it generated 1000 horsepower) switchers was introduced. In 1941, the original side-mounted radiator was replaced by a front-mounted system. With minor modifications, production continued until 1946 and a total of 548 were built, making the VO-1000 Baldwin's best selling loco. Available for the first time in plastic, this all-new HO Scale model will be offered in two body styles; with step guards on the battery boxes, or with extra side louvers and no step guards. As a result of excess heat under the long hood and back-pressure problems in the VO series prime mover, Baldwin experimented with a variety of exhaust stack configurations. All models will feature optional parts for a single smoke stack, four short stacks or four tall stacks to match prototype practice.