Campagnolo's Centaur Rear Derailleur uses an advanced-parallelogram design that assures precise and quick shifting. The carbon/cold-forged-aluminum construction reduces weight considerably, boosts strength and provides a high-tech look. Plus, the pulleys are even made from a special material that renders the drivetrain especially silent. This is the perfect upgrade for your road machine.
An important part of a rear derailleur's job is keeping the chain taut as you change gears. Chain-wrap capacity is a number that tells whether or not a derailleur will be able to do this on the drivetrain you plan to use it on. Calculate chain-wrap capacity with this formula: Chain-wrap capacity = (large chainring - small chainring) + (large rear cog - small rear cog). Example: 44/29 chainrings and a 11-28 cassette: (44 - 29 = 15) + (28 - 11 = 17) = 32-tooth chain-wrap capacity.