Aircast Bivalve Ankle Brace - Air Stirrup Classic The Aircast Air-Stirrup Classic Ankle Brace 81-02C is an innovative brace for the treatment of ankle sprains and injuries. Equipped with a Duplex system with pre-inflated air cushions, it reduces swelling and accelerates healing. The semi-rigid valves offer stability and comfort, while the design with velcro closures makes application easy. It is latex-free, suitable for those with allergies, and supports both sprains of various levels and chronic instability. The brace is comfortable, breathable and based on over 30 years of research.