Kalmbach 12663 Model Railroader's Layout Design and Planning Modeling the Transition Era by Tony Koester Traffic Lights Treal Hobby (X002I3CQG9) 8T 27T Overdrive Treal Hobby (X002I3CQG9) 8T 27T Overdrive Gears for Capra UTB and SCX10iii 4mm hardened steel polished shafts The 1940s to 1950s transition era has long been the most popular modeling era and this book gives an overview of how railroads operated Modeling the Transition Era from Kalmbach Publishing and authored by noted Model Railroader Magazine contributor Tony Koester is an in depth look at the era when most railroads were making the switch from steam to diesel locomotives