Name:ZALOPA Brand Semi-Metallic Resin Disc Brake Pads Suitble For:Hayes:Sole, MX2, MX3, MX4, MX5, CX5, GX-C, GX2, BENGAL HELI X3 X5 Quantity:4 pairs (8 pieces) with 4 springs Material:Semi-Metallic Resin,90-95% Resin,5-10% Brass * 100 % Brand new and high quality * Compact,lightweight and durable * Ultimate brake power Silent * copper granules,Better heat dissipatio * perfect surface spray treatment better than other normal disc brake pads * Parts for bicycle Slim size,very convenient to use without any difficulties. At least 2 times than other normal disc brake pads. Tested By TUV Rheinland with EU Standards,EN14766:2005