Park Tool Chain Gang Cleaning System. Features: Chain scrubber machine easily cleans dirty chains with a multi-brush system that applies chain cleaning solution Updated version allows for the scrubber handle to be used on either side. Certain E-Bikes do not allow backwards pedaling when being cleaned Cassette/derailleur brush gets into hard-to-reach spots, scraper on handle helps to deal with tough grime Includes: CM-5.3 Cyclone Chain Scrubber Machine GSC-1 GearClean cassette/derailleur brush 8oz bottle ChainBrite cleaning solution