The D&RGW had a number of dual gauge idler cars, including some early wooden ones which were made from standard gauge flat cars. On the Valley line, they used an ex-Uintah tender as an idler (it is now the tender for OM), the D&RGW even equipped some standard gauge cabooses with dual gauge couplers for use between Salida and Leadville. The remaining dual gauge idlers were built in the late 30s and were replacements for some of the early wooden versions. In addition, many standard gauge and some narrow gauge engines were equipped with dual gauge couplers.