Shimano GRX BR-RX410 Hydraulic Disc Brake Caliper - Front Flat-Mount W/Bracket 140/160mm Rotor Assembled 160mm BLKShimano GRX BR RX410 Hydraulic Disc Brake Caliper Front Flat Mount W Bracket for 140 160mm Rotor (Assembled for 160mm) Black. The GRX BR RX410 disc brake caliper brings a new level of control to gravel cycling with enhanced modulation and a quicker initial braking point. And despite its compact construction the system is quieter and easier to maintain. GRX BR RX410 flat mount 2 piston brake caliper has 10% wider pad clearance to decrease brake