Life Boost Removable Decorative Blackboard Chalkboard Wall Paper Sticker Decal 78.7 x 17.7in (Green) 1. These blackboard sticker are really easy to apply on walls, refrigerators or kitchen cabinets. 2. Material: PVC; Color: Black/ Green/white; Waterproof. 3. It's recommended to clean the wall leaving no dust and dirt before applying the stickers onto your wall. 4. Size: 78.7 x 17.7in (The size is one-sheet without any design). 5. Please don't use it on freshly painted walls; Place on a smooth flat surface such as walls or windows etc.