Mitox Grass Trimmer 25C-SP SelectMitox Grass Trimmer Model 25C SP Select From JBW Smith the Mitox Grass Trimmer for the domestic gardener. The Model 25C SP quality grass trimmer is powered by 25. 4cc engine. The grass trimmer comes with a clever split shaft system so that when all your garden work is done this allows the machine to be easily separated into two for convenient transport and storage.