The patented, proprietary two-speed, heavy-duty transmission is built tougher with over-sized gears and with needle and ball bearings throughout. The Blade Spindle assembly is built stronger with a forged spindle shaft for optimum strength and a die cast aluminum housing that dissipates heat faster. The powerful professional-class engine starts quickly and is always up to the task of all day mulching and mowing, and at speeds up to 5 mph.