Laser-cut double disc ground 420 high carbon stainless steel. Direct-replacement brake rotors; do not require any extra parts, bolt on just like a stock brake disc. Full-floating design rotors have an aluminum center carrier. Improves brake lever feel and modulation. Rotors cool as they rotate to lower brake operating temperatures. Design is self-cleaning, removes water as it rotates. Less tendency to warp. Manufactured in Spain. For maximum braking performance and rotor longevity, Galfer recommends using Galfer brake pads with Galfer rotors..