AeroShell Piston Engine Oil W120, were the first non-ash dispersant oils for aircraft piston engines. They are designed for certified four-stroke engines, including fuel-injected and turbocharged types, offering stability, dispersancy, and anti-foaming capabilities. By blending non-metallic additives with high viscosity index base stocks, these oils prevent metallic ash residues in combustion chambers and on spark plugs, avoiding pre-ignition and engine failure. Aeroshell Oil W 120 is not suitable for automotive engines. For automotive engines adapted for aircraft use, consult the engine manufacturer or conversion agency for oil recommendations.