If your vehicle is equipped with an IR DVD system, these will work for you! Passive noise-cancelling headphones make use of the noise-canceling characteristics of their materials that are much like the soundproofing materials used in home theater systems. These passive noise-canceling headphones are composed of layers of materials packed with high-density foam and other noise-filtering materials. These soundproofing materials are very effective against high frequency sounds. They are able to reduce noise levels to about fifteen to twenty decibels.