Sta-Bil Diesel Formula Fuel Stabilizer is a diesel additive that keeps fuel fresh for quick, easy starts and maximized for engine performance. Designed for use with all diesel engines and all diesel fuels, Sta-Bil Fuel Stabilizer prevents sludge and sediment formation, cleans and lubricates fuel injectors to improve performance, and helps remove water that microbes and algae require for growth. For in-season use: 1 oz. treats up to 10 gallons of diesel fuel. For storage use: 1 oz. treats up to 5 gallons of diesel fuel. 128 oz.