Strengthen the construction of a curtain with the S-fold blockout curtain liner. This extra layer protects the curtains from dust and grime. Even more, the liner blocks out light and sound to help create the right ambience for relaxing and sleeping. It also keeps the room warmer when the exterior temperatures drop. You can use this liner with the curtains in bedrooms, livingrooms and kids? rooms. This white blockout curtain is made of pure polyester, thats lightweight and strong.