Fitment
Will this fit?
Fitment data still being indexed for this product. Ask BuildBot for a fit-check against your vehicle.
The compound
Circo M119.
A carbon-metallic compound built for rally and circuit work, and the standout in the Circo range for short events. It publishes 0.48–0.51 friction from a 50°C floor — near race-compound bite that is already working on a cold first lap. Circo describe it as more forgiving to drive than M127.
Operating range50–800°C
Friction µ0.48–0.51
Pad life'Very low wear rate'. No numeric figure published.
Rotor weargentle
Cross-brand equivalents
Run something similar.
These are the compounds we stock for the AP Racing 4-pot RD42 (CP3215 D40/D42) whose published friction and operating temperature come closest to Circo M119. They are a starting point for switching brands — not a guarantee of identical feel, because each manufacturer measures friction on their own equipment.
Project Mu PCR09
Very close300–800°Cµ 0.42–0.55
Project Mu’s Club Racer. A strong trackday pad, but with a 300°C floor it is the range’s worst choice for a cold first lap.
Matched on published friction and operating temperature.
From $409 · in stockProject Mu H16-03
Very close200–650°Cµ 0.45–0.60
Project Mu’s GT and TCR-level race compound.
Matched on published friction and operating temperature.
From $470Project Mu H21
Partial match200–850°C
Circuit and endurance racing. Project Mu rate it as kind to the rotor with long pad life.
Matched on published operating temperature only — one of the two brands doesn’t publish a friction figure, so this is a weaker comparison.
From $572Compare every compound for the AP Racing 4-pot RD42 (CP3215 D40/D42)
Fits the same caliper
More pads for the AP Racing 4-pot RD42 (CP3215 D40/D42).
Pairs well with
