THIS LISTING IS FOR THE TRANSAXLE NOT THE MANUAL PICTURE IS FOR REPRESENTATIVE PURPOSE. THIS UNIT SHOULD BE INSTALLED BY A CERTIFIED MECHANIC. Hydrostatic Transaxle – A multi component assembly including a gear case and a hydrostatic transmission. Hydrostatic Transmission – The combination of a hydraulic pump and motor in one housing to form a device for the control and transfer of power. Hydrostatics – Engineering science pertaining to the energy of confined fluids. Integrated Zero-Turn Transaxle – The combination of a hydrostatic transmission and gear case in one housing to form a complete transaxle. Note: a transaxle performs both the gear-changing function of a transmission and the power-splitting ability of an axle differential in one integrated unit. A transmission performs the gear-changing function only, delivering power via a single output shaft at the back of the unit. All Hydro-Gear products can be identified by the label attached to the product depicting the model and serial number. You will need this information when asking for specific assistance with service and/or repair needs.