From Pagid USA:
COMPOUND CHARACTERISTICS

RS 4-2-1 BLACK
A high performance compound with low fading characteristics and high cold friction. The most comfortable medium friction sport compound. Rotor friendly and OE on various Ferrari, Lamborgini, Lotus, Bugatti and Corvette (Callaway) models. Suitable for street and light track use.

RS 4-2 BLUE
A medium friction racing compound with good cold friction and fading resistance up to 500°C ( 930°F).
The 4-2 compound has an acceptable rotor wear rate and a very good modulation (adjustment). It is a Classic Rally compound and is used also for small Single-Seater ( F3, F-Ford, Club Racing and Showroom Stock).

RS 4-4 ORANGE
This compound has a very good fade resistance and a higher average friction value than the RS 4-2. It is rotor friendly with a predictable, non-aggressive friction behaviour (stable torque). Fading resistance up to 560°C (1.050°F). It is a very good rear compound for Touring Car applications in combination with RS 14 front pads. It's main application is Porsche 911 racing. It is used on either Short Track or Long Distance; also for front and rear axles. It is also used on BMW Showroom Stock, all other Touring-Cars and Single- Seater up to F3.

RS 7 BLACK
Degressive friction curve. Low friction rear axle racing compound, especially developed for front wheel driven cars.

RS 14 BLACK
This is a medium high friction value ceramic type compound with very good modulation, high fade resistance, low heat conductivity, and a good wear rate up to a temperature of 650°C (1.200°F).
It is kind on discs, with visible grooving, but a limitation of hairline cracks.
Applications: NASCAR, CART, F3, Touring cars, GT cars, WSC, Trans Am and Rally.

RS 15 GREY
Very high torque compound. It combines a 20% higher friction value than the RS14 with a slightly increased pad wear.
Needs finesse to avoid over braking the car. Good release characteristic and a quick bedding in procedure.
Although the "RS15" has very good modulation it might have an excessive bite for some applications.

RS 19 YELLOW
Best compound for endurance racing on the basis of the RS 14. A slight reduction of the friction value improves the modulation. Nevertheless, the friction value is enough for cars without power-assisted brake system and ensures comfortable low effort on the brake pedal. Constant temperatures up to 600°C (1.100°F) are possible. The combination of friction value, fading stability and low wear rates on pads and discs realised with this pad compound is unmatched up to now.
Due to its outstanding wear rate and driveability also used at many sprint races.
Application: All endurance racing cars from group N (Speed-WC, Grand Am Cup) up to GT and Sport-Prototypes.
A multiple winner of Daytona 24h, Le Mans 24h, Sebring 12h, Spa 24 h, Nürburgring 24h, often with no pad change and usually no disc change.

RS 29 YELLOW
New endurance compound. Improved version of the RS19. This compound combines the outstanding wear rate of the RS19 with a slightly higher coefficient of friction. For the time being only available in certain applications.

Sport pad - dark blue
This is a high performance compound with low fading characteristics and high cold-friction. The most comfortable medium friction sport compound.
The Sport Pad is rotor friendly and suitable for street and light track use. Available for most Audi, BMW, Porsche and VW applications.
PAGID "S" Brake Pads are dipped in a anti-corrosion blue paint, with a layer also on the friction surface. This paint coating will disintegrate during the first braking applications without any loss of friction compared to our other non-coated compounds. In addition a majority of the "S" Line is standard with anti-noise shims.

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