The Craftsman hydrostatic transmission is made by the Sears Corporation. The transmission is used in Craftsman lawn tractors and riding mowers. It is a sealed unit that contains hydraulic fluid. The transmission has a pump that circulates the fluid through the transmission. The fluid pressure is used to move the pistons in the transmission. The transmission has two gears, low and high. The low gear is used for mowing and the high gear is used for transportation.