Pentosin FFL-4 is the only approved first fill and service fill transmission fluid for the new generation of BMW double clutch gear transmissions (DCT). Pentosin FFL-4 is founded on a fully synthetic base oil technology for safe operation at even the highest thermal load. FFL-4 features a special clutch friction performance which makes it mandatory to be applied solely to the double clutch gear box, do not mix with any other gear oils.