A must-have for modelers, Santa Fe Power in Color Volume 4: Electro-Motive Six-Axle Hood Units from Morning Sun Books is the fourth book in a series about the diesel locomotives of one of North America's most popular railroads. Author Ed Mackinson covers the Santa Fe's premier power, the six-axle Electro-Motive roadswitchers were the backbone of Santa Fe's mainline freight service. Volume 4 features them all, from the SD24s of 1959 to the Warbonnet SD75Ms of Santa Fe's final days!