Thinsulate TC3303 was special fabricated for vehicle, much lighter than other Thinsulate products! 3M™ Thinsulate™ Acoustic Insulation TC3303 is a cavity filling solution for automotive sound insulation applications.
I've not known longevity of the product but the shipping from China was difficult to disassemble. Product seems authentic though I do not know how to distinguish, at least it has 3M embossed logos.