About 48" long runs on R-3 curves according to MTH. Anything below 8’ will not work. Regrettably selling my Challenger, my curves and grades are too much for it, Beautiful train with great sound. “Chatter” at idle and even more sounds if you have the MTH DCS remote. I’ve added smoke deflectors and replaced all 6 traction tires. Everything works as it should. The sound plug is a little loose and needs braced to get the sound to stay on. Missing one tender lantern housing on the right side but still works. I never had the original box. Selling to replace it with a new USA Heritage Missouri with sound.
https://www.youtube.com/watch?v=Yig-DqSIj04