Shimano GRX RD-RX812 Shadow+ 11 Speed Rear Derailleur - Rear Derailleur - 11 Speed - Black - Mid Cage - 42T Max Replace Images which fit underneath the peak

which fit underneath the peak when not in use

Preps surface for use with TLR-1

Narrow Wide tooth profile eliminates chain drop with the perfect chain mesh fit

Correct use of your bicycle's gears will allow you to fine tune any training session without having to manually adjust resistance

Servo Wave

Shimano GRX RD-RX812 Shadow+ 11 Speed Rear Derailleur - Rear Derailleur - 11 Speed - Black - Mid Cage - 42T Max Replace Images which fit underneath the peakWith 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. The RD RX812 rear derailleur is compatible with mtb cassettes with a 42T low sprocket max.