TRP HY-RD brake is Pronounced High Road... The latest iteration of our industry leading efforts to bring hydraulic performance to the developing road/cross disc market, the TRP HY/RD brake is an OPEN hydraulic system that is compatible with Shimano and Sram road shift levers.  TRP HY-RD Flat Mount Calliper Features True 'plug-and-play' compatibility with existing cable actuated systems Hydraulic reservoir provides automatic pad wear adjustment TRP's own ultra-grippy semi-metallic pad that are Shimano M525/M515 compatible allowing for further customization Compound works well in dry conditions but may wear quickly in wet/muddy conditions Available in black anodised with polished cap or polished with black anodised cap We always recommend using 160 front Available in Post Mount or Flat Mount fitting