The POC VPD Air Knee is lightweight, highly flexible & provides reliable protection. Their VPD (Visco-elastic Polymer Dough) material is soft & flexible but absorbs energy & hardens on impact for maximum protection. This pad is housed in a reinforced breathable stretch fabric & stays securely in place thanks to the anti-slip neoprene liner & elasticated Velcro top strap. The low-profile design enables them to fit easily under trousers & helps improve the overall comfort of the pad. Features Lightweight ventilated VPD protection Low profile design Reinforced stretch fabric Breathable Elastic strap for a secure fit Come as a pair