Featuring the latest evolution of the exclusive Sidi Vertebra system the Vertigo 2 has a host of other features that will continue to make it the sales leader of the sport boot segment Vertebra System adjusted via Sidi’s exclusive Tecno VR closure system helps to protect the rider’s Achilles tendon A single nylon ankle support brace for extra support. Double stitched in all high stress areas Bolt on replaceable, adjustable and aerodynamic nylon scuff pads on the toe Closable air vent. All bolt on parts are replaceable. Dual compound sole Lined with anti-abrasion Cambrelle in the foot area for comfort, the upper is lined with Teflon mesh which prevents complete absorption of water and sweat. These materials will not retain water or sweat on the inside of the boot. DuPont polymer toe shift pad. Perforated Teflon treated nylon lining. Shock absorbing heel cup. Padded Achilles area is very comfortable. Reflective panel at the heel. Pleated panel in the key front-arch area of the boot for maximum comfort. zipper and Velcro closure system.