I have a siginificant amount of knowledge about small engines, new and old, as far as their composition and how one should work. I am very familiar with Briggs & Stratton, Tecumseh, Kohler, and Kawasaki. I rarely work on them, but as far as parts go, I'm very proficient. I also know a lot about trimmers, hedge trimmers, polesaws, blowers, chain saws, etc, specifically the brands Echo, Stihl, Kawasaki, and Redmax. I have also worked with the commercial lawnmower brands Scag, Yazoo-Kees, Encore, and Hustler, and with the more common "box-store" brands AYP, MTD, and Murray.