The first tractors designed for the ability to fit between rows of crops were made by International Harvester (IH), with development beginning in the 1920s. The first row-crop tractors made by IH were called "Farmalls". The cultivator mounted in the front so it was easily visible. Additionally, the tractor had a narrow front end; the front tires were spaced very closely and angled in towards the bottom. The back wheels straddled two rows and it could cultivate four rows at once.