a Fordson. At least 3 companies offered crawler conversions, and others offered enlarged cleats, including the "overgrown tire chain" type that had led to crawler development not long before. Several companies converted Fordsons to road graders; the Wehr (video) is well remembered. The first tricycle cultivator version of the Fordson was available as an aftermarket conversion by the Moline Implement Company as early as 1920 or 1921, which was 3 to 4 years before the Farmall was introduced, a full decade before Dearborn prototyped the Fordson All-Around, and a full decade and a half before Ford Ltd produced that model. It lacked those tractors' high clearance but was otherwise prescient. An economically significant concept is illustrated by kits such as the Dearborn Tractor Control. Its attachments let the person riding the towed implement control the tractor from the implement seat. Such a setup was offered for the Fordson by at least 3 aftermarket suppliers. It was reminiscent of earlier mechanized efforts such as the Detroit Tractor, Moline Universal, and Allis-Chalmers Model 6-12 in that it represented the most literal kind of horse replacement (in some suppliers' cases, even retaining the reins as the control method). But besides providing mere comfort and familiarity for farmers accustomed to working with horses, it also neutralized an economic disadvantage of the tractors of the era. With horses, one person could control both the motive power and the implement, but with a tractor, two were required, because the tractor required a driver and the implement, in many cases, required an operator. Most implements of the era were legacy horse-drawn equipment (a fact that Harry Ferguson had to battle in trying to sell his system of tractor-specific implements during the 1920s and 1930s). Setups such as these cut back the man-hour requirement to match that of the horse—while the tractor's multiple horsepower and lack of daily, year-round feeding ("eats only when it works") continued to beat the horse economically otherwise. The two-person requirement was often not a problem on farms that had large families; a son or daughter was usually available for duty. But the farm help problem was felt keenly on many other farms, especially during the world wars. Technological advancement eventually made it standard for one person to control both the tractor and implement, via the growing suite of hydraulic and electrical controls, especially after World War II. In 1926 a corporation called Snow-Motors