Speedplay and Sidi, together at last. This Sidi Genius 6.6 Carbon Speedplay Shoes sport the all-new carbon fiber Speedplay-specific sole. The sole is Speedplay-approved, and will save you nearly a quarter-pound, and three millimeters of stack height compared to using adapters. As if that wasn't enough reason to celebrate, Sidi has also redesigned the heel retention system to provide a more comfortable, adjustable, and secure fit.

• High Security Velcro on the straps is just like the Velcro you love, but way beefier for a true locked-in feeling in high-torque situations
  
• Easy-to-use caliper buckle makes on-the-fly adjustments simple and effective
• Padded tongue and Soft Instep Closure System make long days more comfortable
• Replaceable heel pad provides traction off the bike