The Shimano BL-MT501 Bled Brake Lever/BR-MT520 4 Pot Post Mount Caliper are excellent value, fully bled, hydraulic 4 Piston disc brakes with an easily adaptable post-style caliper. This fully bled lever and calliper comes without adapters or rotors giving you the freedom to customise to suit your bike. Can 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 160mm, 180mm and 203mm. Shimano BL-MT501 Bled Brake Lever/BR-MT520 4 Pot Post Mount Caliper Features Opposed high power 4-pistons design in two different diameters reduces leading effect and optimal pad wear increases braking control Two piece calliper design is both ridged and durable Hinged clamp design Ergonomic alloy brake lever for optimum comfort and performance Mineral oil brake fluid is non-corrosive and less hazardous than conventional hydraulic brake fluid Shim-less mounting system allows for quick installation and setting up I-Spec-II compatible Brake lever features reach adjustment for perfect custom fit The kit also contains resin pads (can be used with sintered and Ice Tech pads), plus spare olives and insert should you wish to adjust the length of the cuttable hoses Hose length: 1700 mm