The Competition Clutch Stage 4 - Strip Series 1620 Clutch Kit, available with a double spring, six rivet carriage is good for ease of gear transition with higher horsepower. This disc complimented by a performance pressure plate provides 250% increase in torque capacity. The 1620 Series kit includes a performance pressure plate, a six puck high torque sprung disc with Ceramic buttons, all applicable bearings, and the appropriate alignment tool. PartNumber : comp15030-1620 Description : Strip Series 1620 Clutch Kit 2004-2012 Subaru Impreza WRX STI H4.2458cc Drivetrain::Clutch Kits - Single 2007 Subaru Impreza WRX STI Limited H4.2458cc Drivetrain::Clutch Kits - Single 2011-2012 Subaru Impreza WRX STI Limited H4.2458cc Drivetrain::Clutch Kits - Single 2010 Subaru Impreza WRX STI Special Edition H4.2458cc Drivetrain::Clutch Kits - Single