All of our Tune Up Kits include Original Equipment Manufacturer (OEM) parts to perform a simple tune up. Toro TimeCutter Series Tune Up kit includes air filter, fuel filter, oil filter, spark plugs, oil and a set of new blades. All parts are Genuine Toro, Kawasaki and NGK. Nothing in this kit is aftermarket. The oil is specially formulated for Kawasaki FR engines. This kit is customized for the following models: SS4260 TimeCutter Zero Turn Mower (Model 74626), SS4235 TimeCutter Zero Turn Mower (Model 74625), MX4260 TimeCutter Zero Turn Mower (Model 74640), Z4235 TimeCutter Zero Turn Mower (Model 74366)