I have ran this stuff all season in a Shindaiwa T262 trimmer. I do lawn care and run the trimmer for hours a day. Pulled the muffler a few days ago and the piston exhaust side is spotless. Exhaust port is clean and spark arrestor screen had nothing on it. Last year I ran saber at 80:1. End of the season the piston was stained pretty good and had to scrap the exhaust port out through it was not blocked up bad it still had a considerable amount more than the red armor has. So red armor does what it says from my experience by cleaning the piston stains off and keeping it clean.