Yes, they will clank if they are installed improperly. But if done correctly, they will not clank so you will not hear metal on metal. As DiMarco mentioned, they will last forever as the rubber ones tend not to.
4.5” Hardin Marine polished stainless exhaust flaps
Part number 410-280176
Used for 30 minutes in fresh water (Parker, AZ) Perfect condition
$200 obo
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