AUPOON(TM) Chalkboard Contact Paper Blackboard Wall Sticker for Home and Office Kid's Teaching Materials Size:18 * 79 inches;Thickness 0.12mm.(0.12mm can make the writing more fluent) Easy to apply, easy to remove,will not damage the wall. Easy to keep clean,wet cloth to wipe will not leave a mark (PP material) Simply to cut length or shape for a custom application. Through Europe and the United States safety standards for testing;In line with the international children's safety standards. Guarantee:If you don't like our product,you can return them within 30 days and get the refund.