AHL Bicycle Semi-metallic Disc Brake Pads for ZOOM DB280 DB550 DB450 DB350 Excellent braking power and quiet braking in wet & dry conditions Medium hardness and better heat dissipation,long lasting performance Using the best semi-metal material,high wear resistant,effectively protect the brake disc Smooth and compact braking,comfortable braking feeling with low noise Quality Assurance!If you are not satisfied with our products,we accept all of the return,replacement or refund requests