High Materials : Made from elastic materials with excellent heat and oil resistance, ensuring stable in extreme conditions for safe brakes systems . Wear Resistance : Rigorously tested for outstanding pressure and wear resistance, maintaining effective sealing under heavy use to extend brakes component lifespans. Resistance : Designed with resist properties to withstand chemical exposure, protecting brakes in mountain and road biking environments. Excellent Elasticity & Flexibility : Features elasticity to absorb shocks and vibrations, ensuring responsive braking for a smoother and safe ride. Package includes: 5 Pairs Sealing Rings