Park Tool GSC-3 Drivetrain Cleaning Brush

Specially designed brushes for cleaning hard to reach areas on most bicycles

• Dual-sided brush specifically designed for cleaning hard-to-reach areas of the bicycle drivetrain
  
• Long, stiff bristles are narrow enough to reach between the gears of tightly-spaced modern cassettes
  
• Slim contoured end is capable of picking grit and grime out of tight spaces such as derailleur pulley wheels

WARNING: California Proposition 65

This product contains chemicals known to the State of California to cause cancer, and birth defects or other reproductive harm.

https://cambriabike.com/pages/warning-california-proposition-65