3D Acoustic designThick, 2 inch foam can be used to absorb lower frequencies to control and trap bass; and to control and trap echoesproviding the ideal level of moderate sound control on walls or ceilings Environmental and safetyThese acoustic foam panels are Made of quality polyurethane High density flame-retardant foam material,odorless,non-toxic, fireproof, durable, efficient and safe to use and also passes flame retardancy requirements Expands quickly Our foam panels come compressed in a vacuum package and quickly recover to normal size, either by placing in a well ventilated place for about 24-48 hours or soaking the foam in water for one minute then wringing the water out and using a hair dryer or letting it air/sun dry Easy to InstallThese studio sound absorbing panels can be used as acoustic cover for walls, ceilings and doors, just easily attach it with staples, nails, screws, tacks or glue 100% satisfaction shoppingThese soun