Get the advantages of propane without sacrificing power and features. Help reduce emissions and fuel costs while extending engine life. Increase visibility, stability and vaporization capacity with the single 43.5 lb. tank mounted behind the seat. Eliminate evaporative emissions and fuel contamination, theft and spillage with the fully sealed system.The Z Master 5000 Series zero turn mower has a Kohler® Command Pro EFI Propane Engine with 60" (152 cm) TURBO FORCE® deck. Model shown 74978.