4 Pairs Kevlar Pads for Hayes HFX 9 HFX-Mag HFX-9 MX1 Disc Brake MTB DH XC Bike Brand: DiscoBrakes Contains Kevlar brand fiber developed by DuPont 4 Pairs of Disc Brake Pads (8 pads + 4 springs) Improved strength and performance with Kevlar in medium density pads Excellent braking power