HP Ultra is a fully synthetic 2-cycle engine oil specially suited for high performance chain saws and power tools. This oil has outstanding engine cleaning characteristics, plus “ultra” superior lubricating qualities in comparison to other 2-cycle engine oils. It is ideal for use in STIHL 4-MIX® engines. This oil is biodegradable, degrading by 80% in 21 days.2.4 oz. bottle makes 1 gallon mix
5.2 oz. bottle makes 2 gallon mix
6.4 oz. bottle makes 2 1/2 gallon mix
12.8 oz. bottle makes 5 gallon mix