Sidi HYPER EXTENSION BLOCK SYSTEM
Replacement Hyper Extension Block System for the Sidi Crossfire 3 SRS Boot.
The Crossfire 3 has an articulated joint on the ankle, called “HYPER EXTENSION BLOCK”, with completely revolutionized technology. It prevents the hyper extension of the ankle, the instep and the posterior tendon when the leg is flexed forwards or backwards. This technology guarantees the rider’s safety interlocking system.