For outstanding lubrication of your air-cooled, four cycle engine, choose Stihl® tech 4 plus oil. Its versatile formula is specially designed for pistons, rings, bearings and valve engines. In addition to delivering protection against wear, tech 4 plus Oil also keeps the engine running cool, clean and free from rust, corrosion, sludge and varnish build-up. Use it in a variety of engines, including garden equipment, small tractors, log splitters, compressors, steam cleaners, pressure washers, pumps and generators.