Why? Because you read that somewhere and you're simply repeating it? Because you've actually done that? Because you drank some deadening Koolaid?
20 sqft? Really, is that based on your doors or what? If not, which doors? Doors in general? Which part of the door(s) are you referring to?
Furthermore, you simply named a manufacturer/seller of car audio-specific vibration and noise control products. How far is that going to get anyone?
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