ShimanoGRX RD-RX820 2x 12-Speed Rear Derailleur(Return to Product Page)

Once installed and adjusted, this derailleur shifts with typical Shimano perfection.

Note that if routing internally, that is, you have no braze on stops, you will have to buy a shift cable set with long enough housing to reach from the lever to the adjuster on the derailleur.

The short sections Shimano provides with the levers are useless if you have this situation.

I ended up using the inner cable that came with the shifter but bought a cable set just to get a section of outer cable that was long enough to get from the lever, through the frame and to the adjuster on the derailleur.