Shimano GRX RD-RX400 Rear Derailleur 10 Speed 36T Max Medium Cage Shadow+ BF PSI Combining breathable and moisture-moving fabric

Combining breathable and moisture-moving fabric across the chest area creates additional turbulence on the jersey surface to reduce air resistance and increase your speed

Choose from 7 different output modes

steel construction with an allow sleeve for increased stiffness

Consistent Spoke Lengths: The all-new straight-pull hubshell allows for the use of a single spoke length for any given rim diameter

A state-of-the-art high-pressure molding process used to produce complex-shaped carbon fiber components creates a unique two piece saddle frame that yields the perfect balance of support and comfort

Shimano GRX RD-RX400 Rear Derailleur 10 Speed 36T Max Medium Cage Shadow+ BF PSI Combining breathable and moisture-moving fabricWith an integrated chain stabilizer mechanism, the SHIMANO GRX derailleur provides a quieter experience and shifting security and precision on mixed terrain. For rides on smooth surfaces, the derailleur features and ON OFF switch for the chain tensioner. FEATURES Silent and uninterrupted rear shifting on rough terrain Adjustable chain stabilizer prevents chain slapping and drops SHIMANO SHADOW RD+ Smooth and reliable mixed surface shifting Switch