Alpinestars Vapor Knee Protectors (Large/X-Large) (Black) Innovative, ergonomically optimized Vapor Knee Protectors are made from light, breathable materials and optimized, robust outer protection structures to provide a close fit, superb articulation and greater impact performance. CE-certified protection systems utilizing robust protective structures and impact absorption padding. Thermo-formed polymer material construction offers improved impact performance. Highly ergonomic design improves streamlining while providing crucial protection for MX and off-road riding. Intelligent fastening systems offer greater flexibility, customization and prevents side rotation.