Shimano 8170 Di2 Rh Sti W Bk Coupler & Receiver Locks Lens Size (mm) : 131 STLHD 2004 XL Lens Size (mm) : 131 Made to replace the sock liner in roomy to moderate fitting athletic and outdoor footwear Your time on the bike is precious let Shimano make it even better Features The wireless connection provides a clean cockpit enhancing the aerodynamic effect and easy maintenance Wider pad clearance decreases brake noise Maintenance friendly bleeding process Unparalelled ergonomic features such as raised hood peaks on levers Brake control is optimized with light and smooth lever action Enhanced modulation thanks to an expanded braking control area Compatible with wireless or wired connection