8 ounce bottle of Stanadyne Diesel Fuel Additive Performance Formula will treat 30 gallons of fuel. Stanadyne's brand boasts the following: more power and performance, improved cetane, and lubrication. It also cleans and protects your engine, while providing cold weather protection. It is compatible with ULSD and B20 and it can increase overall fuel economy. Stanadyne meets all diesel system requirements. This specific bottle is also compatible with all diesel Volkswagen engines.