"If you are storing a gasoline vehicle or piece of equipment for 30 days or longer, we recommend you continue to use STA-BIL® Fuel Stabilizer. It will keep fuel fresh for up to 12 months.
If you are looking for an additive that will help protect your vehicle or equipment from Ethanol-blended fuels, you should be using new STA-BIL® Ethanol Treatment more regularly to help further protect against corrosion, clean your fuel system, and remove water at every fill up."