I have used their sound deadening material. It's like a 1/8 inch thick piece of tar paper with self stick adhesive. It's very heavy in weight. The adhesive works OK on very clean metal. It is intended to reduce vibration on large pieces of sheet metal. It is a sound deadener, not a sound absorber. Best use would seem to be to stop rattles and buzzes from really loud audio speakers ( sub woofers ). I lined my floor pan with it hoping to reduce road noise, but it didn't make a noticable improvement. I have no experience with the hood material.

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