The Shimano GRX ST-RX715 / BR-RX410 pairs a 12-speed Di2 dual-control lever with a hydraulic disc brake caliper in a single rear unit. The ST-RX715 uses wireless electronic shifting compatible with Shimano Road Di2 drivetrains, while the BR-RX410 flat-mount caliper delivers a quicker initial braking point and 10% wider pad clearance compared to previous GRX generations.

The lever includes a reach adjust mechanism to fit different hand sizes, and button functions can be remapped through Shimano's E-TUBE app. The BR-RX410 ships with L05A-RF resin pads featuring a finned backplate for better heat dissipation during extended descents. One-way bleeding keeps hydraulic maintenance straightforward, and the system runs on mineral oil. A disc brake rotor is not included.

Quick Facts

Feature	Specification
Drivetrain Speeds	12
Shifter Compatibility	Shimano Road Di2
Brake Caliper Mount	Flat Mount
Hydraulic Fluid	Mineral Oil
Pad Compound	Resin (L05A-RF with finned backplate)