The product line continued to be refined and expanded. The chugger / smoker was redesigned and moved from the tenders into the engines. The advantages included eliminating the separate motor (power drain and cost) and ensuring precise (geared) synchronicity of the chugging with the rotation of the drive wheels. DC versions of the engines were offered in the 1949 line. Two different engines (the other AC) could be controlled with nominal independence on the same track. Diesels, not offered since 1940 were offered in the 1950 line.