Are car sound insulation cotton, thermal insulation film and thermal insulation cotton the same? Is it one thing or three?

Not the same. If it is powerful, the functions of sound insulation cotton and heat insulation cotton are combined into one. It is a patented product called Super Windsor. It is not only sound-absorbing and heat-insulating, but also flame-retardant. It is mainly used for car doors, trunks and roofs. The thermal insulation film is also a patented product and becomes the hood insulation film, which is used on the hood. Materials, shapes, functions, and applicable environments all have standards and are different things.