For those of us who want to replace the Boxster dual mass flywheel with a single mass aluminum flywheel, SPEC now makes a 'sprung hub clutch disc' for that.
www.lindseyracing.com has it available---call Dave Lindsey since he does not have it posted on the WEB site yet. A solid hub clutch disc is all that has been available, which results in a lot of rattling noise of transmission gears, but only in neutral.