Crye Combat Knee Guards are lined with SmartFlex, a lightweight and flexible pad that hardens on impact, increasing shock absorption without adding weight. SmartFlex pads are waterproof and machine washable. Features flexible cap for mobility and durability. Exceeds impact protection requirements of test standard EN14404 and Berry compliant. Vented for airflow, lightweight and durable construction, and Made in U.S. from U.S. materials.