Storing engines with ethanol-based fuel for long periods can seriously corrode parts. STA-BIL's Fuel Stabilizer offers the best protection against this damage and more, for worry-free storage and longer life in your equipment. Keeps fuel fresh for up to 24 months during storage. Keeps fuel fresh for up to 24 months during storage. Eliminates the need to drain fuel prior to storage. Ensures quick, easy starts after storage. Prevents gum and varnish build-up. Effective in all gasoline, including Ethanol blends.