S3 pads are suitable for both the front and rear brake while on off-road applications the S3 is only recommended for the front brake. The S3 series is designed for low abrasive interaction with the rotor and quieter braking due to the ceramic composite material. It has an HH friction rating and performs better at higher temperatures than the AD compound. Friction materials contain metal-ceramic with a bronze-graphite and non-metallic friction additives are spread evenly on the base fine bronze body to achieve optimal friction properties. Fits: Kymco Xciting 500iR 2009-2011