Park Tool CoMB RBS 5 Replacement Sponge for 4000018 5.2 CM

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The rbs-5 brush set includes the large side scrubbing brush, two roller brushes, and two wicking foam blocks The cyclone chain scrubber brushes are replaceable Sidewall brush assembly Includes a complete set of three rotating brushes plus two wicking sponges

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Wicking Sponge Roller Brush Sidewall Brush Assembly