The BikeSmart Toof Brushes are specifically designed for cleaning the grit and grime out of your drivetrain for quieter, smoother shifts. The curved toothed tool cleans dirt and grime from cassette cogs, while the durable nylon brush is perfect for scrubbing derailleur pulleys and chainrings. Use with a rag and a little degreaser to make your drivetrain happy, quiet, and gunk-free.