Campagnolo's Athena Rear Derailleur uses an advanced-parallelogram design that assures quick, precise shifting. The aluminum construction keeps weight low and boosts strength for a rigid assembly. Plus, the pulleys are made from a special material for quieter drivetrain action.
Largest cog this derailleur can handle: 29 tooth
Campagnolo 11-speed components are best used as a system (they're not recommended for use with 10- and 9-speed Campagnolo components)