The sound proof panels have double-sided tape behind .Easy to Install.Just rip down the first layer of double-sided tape,you can paste in wherever you . Remarkable sound insulation effect - It can cut dowm noise and ,protect your privacy,aviod the noise effect others.You can more enjoy the time in studio & office. Acoustic Panels are applying for studio&home, entertainment theaters, home offices. Made of environmental friendly, non-toxic, recyclable materials, no irritating odor, it's safe for adults, kids, and pets acoustic panels are designed with beveled edges, which can be spliced into many funny and colorful patterns. It's also easy to cut to meet your needs, perfect for decorating walls, adding a sense of technology and modernity. color:Dark gray :Polyurethane Package Contents: 36 x Acoustic Panels Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.