The Shimano BR-MT420/M4100 features consistent braking performance and reliable stopping power in all conditions. The 4-piston caliper instils greater downhill confidence and control.Deore BL-M4100/BR-MT420 fully bled hydraulic disc brake with easily adaptable post-style calliperRear fully bled lever and calliper comes without adapters or rotors giving you the freedom to customise to suite your bikeCan be used with the revolutionary Centre Lock rotor system which fits easily to Centre Lock compatible hubs; alternatively, conventional 6-bolt rotors can be used all in a choice of 160 mm, 180 mm and 203 mmOpposed 4-piston design reduces leading effect and optimal pad wear increases braking controlTwo-piece calliper design is both ridged and durableHinged clamp designErgonomic alloy brake lever for optimum comfort and performanceMineral oil brake fluid is non-corrosive and less hazardous than conventional hydraulic brake fluidShim-less mounting system allows for quick installation and sett