7-Layer Heavy Duty Blackout Window Covers! Black Ultraflect Nylon- 3 layers of Polyester – Aluminum Fabric – 1/4″ Foam – Canvas   Attaches to windows with Black Industrial grade suction cups in less than 60 seconds Extends your privacy to include your cab area! No more use for curtains! Stores Easily! When ready to hit the road, roll the covers up together and they secure with built-in Velcro straps Aluminum Mylar Radiant Barrier stops the transfer of hot and cold temperature keeping the cab and bunk