ride on zero turn commercial mower, 25.5hp petrol engine, 152-cm (60-in.) Rear-Discharge Mower Deck, shaft drive to the cutting deck through cast iron gearbox and cast iron blade spindle bearing housings. Rotate the height of cut knob to adjust from 2.5 cm to 14 cm (1 in. to 5.5 in.) in 6-mm (0.25-in.) increments. The control levers that operate the hydrostatic transmission have built-in electronic controls to raise or lower the mower deck or disengage the mower blades