The Fitch® Fuel Catalyst is a pre combustion fuel treatment device the purpose of which is to improve combustion. The Fitch® Fuel Catalyst is a true catalyst in that it causes a reaction but is not consumed or affected in the process. Therefore it is not an additive as it puts nothing into the fuel. It is installed in the fuel line of any engine just like a fuel filter. It is a maintenance- free product, which will last for up to 400,000 kilometers or essentially, the life of the engine.