The Marx 400 locomotive was Marx’s entry level plastic locomotive that it sold in inexpensive electric sets.
Introduced in 1952 as a windup and in an electric version in 1953, the 400 was an 0-4-0 steam locomotive made of plastic. Initially, it supplemented pressed tin engines, although plastic eventually overtook metal in the most inexpensive sets. But in 1953, plastic was still somewhat new and novel. So a set with a plastic engine and tender could actually sell at retail for about 10% more than an all metal set.
David Farquhar is a computer security professional, entrepreneur, and author. He has written professionally about computers since 1991, so he was writing about retro computers when they were still new. He has been working in IT professionally since 1994 and has specialized in vulnerability management since 2013. He holds Security+ and CISSP certifications. Today he blogs five times a week, mostly about retro computers and retro gaming covering the time period from 1975 to 2000.