The Alpinestars SX-1 Plasma Knee Protector offers superior impact protection with its embedded Plasma Knee Protector within a highly ventilated semi-rigid frame. It features a Dual Gear System (DGS) for natural knee articulation and comfortable wear. The Nucleon Plasma material is multidirectionally flexible, adapts to the knee, and effectively dissipates impact energy. The dual-density co-injection frame prevents pressure points, ensuring a comfortable fit. Article: Alpinestars SX-1 Plasma Knee Protectors, Size L XL for Men.