The KRAFTSTOFF Fuel Savings Patches work well for lowering fuel costs for heating tanks at homes or companies. There will be an 8-15% fuel savings within the first month of installing the patches on the side of the tank. At least three patches are needed on the heating tank since it is large. The tanks will operate more efficiently when using the Patch. Visit http://howtoincreasegasmileage.com to discover more about the Patch.