STA-BIL Small Engine Pro is a versatile fuel additive product that can be used in both oil and gas to improve outdoor power equipment engine performance. When added to oil, it lubricates and frees sticky valves and pistons, providing a layer of protection in the crankcase and reducing engine noise. When added to gasoline, it helps clean out gum and varnish, restoring lost engine power and reducing rough running issues. This product comes in a convenient 16 fluid ounce bottle, making it easy to use and store for all your small engine needs.