NOTE: Due to shipping requirement, we compressed (vacuum sealed) the acoustic foam for easy shipping. Usually, please kindly give it until 24 to 48 hours for the foam to restore to its normal size.Description:Insulation Mat Acoustic Dampening Heat, Sound deadener Sound Proof StickerProduct parameters:Features: fire retardant, environmentally friendly, self-adhesive, thermal insulationThickness: 3cm thickeness/5cm thickenessLength: 20mStrong sound insulation and absorption performance,heat insulation, damping Reducing energy consumption with strong performance of heat insutionStrong shock resistanceMaking sound more centralized and harmony by changing the way of sound transmissionInstallation Notices:1, Please clean the surface you want to paste.2, Make insulation materials and sheet metal firm fit, damping performance3, Do not cover the chassis wiring or air holes when you installation4, Appropriate use of adhesive tape will strengthen connections effectUse suggestions: This item is in highly densify packaging when delivered. Simply let it in wide open air space for 2-3 days so it will automatically go back to its original shape. Pull it gently by hand if the item is not recovered perfectly.