4 PCS Car Side Window Sun Shades, Light Blocking & Sun Protection Shade, Full Blackout Privacy Curtain for Front & Rear Window, Strong-adsorption Foldable Cover for Most Vehicles (Black). Heat Insulation: This car window shade is made of multi-layer fabrics, which can block the heat from the sunlight from entering the car, significantly reducing the temperature inside the car and avoiding the discomfort of stuffiness caused by sun exposure.