Shimano CALIPER BRAKE, BR-R9100, DURA-ACE, FRONT & REAR, CS-51, 10.5MM SUNKEN NUT, SHOE:R55C4

Comfortable riding with wider tire on rough road
The best balance between rigidity, weight and stopping power
Compatible with 28C tire size
Clear contact feeling with better linearity
Less gap between each arms
Better clearance with wider tire
More predictable, linear braking curve
Sleek design
Stabilizer added between axles work