This is a O Scale 3 rail Baltimore & Ohio Phase 1 F3 A and F3 B unit that is plastic. Both engine are powered and have the TMCC system. These engines have metal grab irons, die cast chassis and trucks, die cast scale fuel tanks, twin fly wheel equipped motors, directional LED lighting, close coupling between units and is highly detailed. The TMCC has electric railroad co. cruise commander technology, improved Railsounds, Legacy Compatible and operating diesel exhaust unit. Minimum diameter track is 36″. These engines were made by Atlas Model Railroad Co. in 2019.