STIHL operating fluids are developed, tested and optimised for STIHL equipment. To this end, chemists, engineers and users work closely to achieve the best results from fuels, lubricants and equipment. STIHL machines, fuels and lubricants undergo comprehensive endurance tests before they appear on the market. All test results are fed directly back into further development processes. STIHL continues to improve products until the optimum level of quality has been achieved - chemically, mechanically and practically - for an outstanding result for people, machines and the environment. You can get more information on the STIHL operating fluids at your local STIHL dealer or on our website: www.stihl.com/the-benefits-with-stihl-optimum-system.aspx