Lever: ST-RX810-R, ST-RX810-L Lever Adjustability: reach Actuation: [brake] hydrualic, [shifter] mechanical Caliper: BR-RX810 Mount Type: flat There are few drawbacks to gravel racing and adventuring, but we'd wager that the largest has been deciding between road and mountain components to build up our drop bar bikes for off-road rallying. With chain slap in the rear, and hoods that aren't built for rugged terrain in the front, things could get scary in the cockpit, but with Shimano's release of its gravel-specific GRX groupset, both of those issues are flown by the wayside. Shimano's GRX ST -RX810 STI Shifter & Disc Brake Caliper offer you shifters that are tuned specifically for gravel riding, with all-new hood designs that feature a more drastic slope to keep you secure when the going gets rough, and a redesigned pivot point on the lever to make pulling the brake all that much more confidence inspiring. Shimano spent the last two years developing the new GRX group that's specifically designed to tackle dirt roads and singletrack on drop-bar machines, and they incorporated plenty of feedback from dedicated gravel racers and enthusiasts in the process. The RX810 mechanical shifters are largely similar in design to Shimano's current road shifters, offering the same light shifting action that rider's have come to know and love. The changes lie in a refined lever shape that improves comfort for mixed terrain riding, as well as a textured anti-slip surface on the levers that improves braking grip and control. The RX810 hydraulic calipers are effectively the same as Shimano's flat-mount road calipers, delivering powerful braking performance of ServoWave, with heat-dissipating Ice Tech brake pads, as well as simple set up and maintenance thanks to One-Way Bleeding technology.