The Allis-Chalmers model B was produced by the Allis-Chalmers Manufacturing company from 1938 to 1957 in the USA and England. With over 125,000 units produced, the model B became one of the best selling tractors for Allis-Chalmers and most loved tractors of its time. Known best for its versatility and adaptability, the model B was also had one of the longest production runs of any tractor by Allis-Chalmers. Over the years of production the B came in several different variations including the Asparagus B, Potato Special, as well as an industrial model known as the Allis-Chalmers IB. It was designed by Brooks Stevens. It had a hp (kW) engine.