Pagid Compound Characteristics




RS 4-2-1 Black

High Performance compound with low fading characteristics and high cold friction. The RS 4-2-1 is a most comfortable medium friction compound and very easy on the discs (rotors). Very popular for brake up grades or tuning. It is OE on various Super Sports Cars among others Aston Martin, Bugatti, Ferrari, Lamborgini, Lotus or McLaren. Suitable for street and light track use such as track days or driving education.


Read more: Pagid Compound Characteristics

Pagid Brake Pads - Compounds and Friction Profile


Graph shows friction vs temperature. PAGID materials are very linear as far as rubbing speed and line pressure is concerned. Since the coefficient of friction is related among other things to the brake disc material we do not show friction levels in this graph. It is only considered to show the difference among the Pagid compounds.


PAGID Friction Compounds

PAGID racing compounds are complex formulations with very high content of ceramic materials. All Pagid materials are asbestos free. The difference to competitor’s ‘metallic’ compounds is the superior thermal insulation and the higher heat resistance of ceramic compared to iron. Ceramic has, to the contrary of iron, very low heat conductivity. Consequently less disc (rotor) temperature goes through the pad into the caliper. We measured up to 60°C (140°F) less caliper temperatures with PAGID pads vs competitor’s pads. This is very crucial when it comes to brake fluid boiling.

Read more: Pagid Brake Pads - Compounds and Friction Profile

Determining Alcon caliper seal diameters

We consistently get asked to help identify which size caliper seals to order.  This guide should help.If you don't have a part number visible on your caliper - you will need to measure the outside diameter of all pistons on one side of the caliper

Look at your Caliper Part number.    Positions with letters designate letters in the part number.  Positions with numbers have numbers.  Parenthesis are optional.  So B(B) could be one letter or two.


Alcon Caliper Part number designator.  B(B) is the piston diameter designation.  See the chart below

CAR 1111 B(B)  22 CC D E F


C - Caliper

A - (A)luminum or (I)ron

R - (R)adial or (L) lug mount

1111 - Caliper Series

B(B) - Piston Sizes (See chart below)

22 - Serial Number

CC - Piston Spec  (A)luminum, (T)itanium, (V)entilated titanium, (S)tainless, (D) Clip in insert, (X) clip in insert ventilated, (E) Low friction coating, (A) Low Friction coating type 2.

D - Abutment Matrial (A)luminum, (S)teel, (T)itanium, or (Z) no abutments

E - Side - (L)eft or (R)ight

F - Location (L)eading or (T)trailing




CAR9850H - would be an Aluminum Radial Mount Caliper Series 9850 with 38.1mm and 41.3mm pistons

CIR5059D - would be an iron caliper 5059 series with 34.9mm / 34.9mm pistons



Alcon Piston Size Chart (8th Digit)



A: 28.6/28.6

B: 31.8/31.8

C: 31.8/34.9

B: 25.4(x6)
D: 34.9/34.9

E: 34.9/38.1

F: 34.9/41.3

G: 38.1/38.1

H: 38.1/41.3

J: 38.1/44.5

L: 41.3/44.5

 K: 41.3/41.3

M: 41.3/46.8

N: 41.3/47.6

P : 44.5/44.5

R : 44.5/46.8

S: 44.5/47.6

T : 22/25. 4/30.2

U : 36/38

V : 22.2/25.4



W: 33.3/38.1/44.5


Y : 27/31.8/38.1

Z : 30.2/34.9/41.3



AA: 25.4(x12)

AC: 25.4(x4)/22.2(x2)

AD: 30.2(x6)
AE: 28.6(x2)/34.9(x2)

AF: 26/31.8/36

AG: 28.6/33.3/36

AH: 40.0(x4)

AJ: 30.2/34.9

AK: 27.0/30.2

AL: 28.6(x8)
AM: 31.8/34.9/41.3
AN: 28.6/31.8/41.3
AP: 28.6/31.8
AR: 28.6/34.9
AS: 30.2(x8)
AT: 27/28.6
AU: 33.3/38.1
AV: 48.0/48.0
AW: 30.2/33.3