CIRCO S99 Performance Trackday Brake PadsCIRCO S99 is a club level competition brake pad compound. It is used for small to medium sized circuit including open wheelers and club level rally competition vehicles where budget is a big part of the pad choice. S99 offers excellent control and wear rates for this level and is considered the all round option in the club level arena as it offers excellent value whilst offering performance levels comparable with higher priced competitor brake pads.