According to the query of agricultural planting network, the specification length of tractor short stairs is 3.8m, the width is 0.48m, and the thickness is 0. 14m. Tractor is a kind of self-propelled power machine which is matched with various working machines. Used in agriculture, transportation, water conservancy, road engineering and construction. In agriculture, it is mainly used to pull and drive various agricultural machinery to complete various field operations and agricultural transportation. The word tractor first appeared in an American patent document about traction steam engine in 1890. Translated into tractor in China, renamed tractor after 1949.