I think you mean single and dual mass flywheel.
Originally Posted by jorg323
What's the difference between a single and double mass clutch?
Either the flywheel or the clutch should contain a damping mechanism (springs). For this reason, a dual mass flywheel will typically utilize a rigid clutch disc (no springs) and a single mass (all aftermarket lightweight flywheels) should utilize a sprung hub clutch.
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