Clutch Masters 02-05 Audi A4/A4 Quattro 1.8T B6 725 Series Street Clutch w/Steel FW - 600ft/lbs TorqRace (TD7R)2 ceramic rigid discs The Clutch Masters FX725 is a 7. 25" (184mm) Twin Disc clutch and is the ultimate in twin disk performance for engines transmissions with smaller bell housings that are focused on drag racing. Clutch Masters FX725 Twin Disc systems are developed from decades of experience in drag racing. Because of the minimal rotational mass the FX725 isn't ideal for the street but with improvements in friction material over the years