The Swissstop Flash Pro replacement pads are for use with Dura Ace, Ultegra, 105, SRAM and TRP braking systems. All Swissstop pads offer top performance on dry rims and even better on wet and offer complete absence of abrasive materials which damage rims. Offering consistent braking (-20C to +40C) with a silent operation the replacement pads are for aluminium rims only. Sold as a set of 4 replacement inserts.BXP: Latest aluminium rim compound. Non sticky predictable linear feel provides improved modulation, power and braking in all conditions.Green GHP II: High performance compound for aluminium rims. Excellent in the dry and unbeatable in the rain. Extremely low pad and rim wear.Original Black: Suitable for less aggressive riding, very good in dry and wet conditions. Specially recommended for rims made of softer alloy material.Supplied as 4 pad inserts for 2 complete brakes