Brian Bell and Chris Opperman. This video shows a wide variety of vintage and modern crawlers at work. Among the vintage models mostly from 1940s and 50s. Covers many makes and models that include Caterpillar, International, Cletrac, David brown, Case, IH Quadtrac, John Deere, Claas Challenger, County and more. Has a full commentary scripted by Brian Bell author of Farm Machinery. Shows crawlers working the land plowing, discing and cultivating. 54 minutes.