GelGems are perfect for any window. They are a mechanically resistant, semi-solid, thermoplastic polymer that stick to windows, mirrors, glass dividers or any other glass surface. GelGems are washable and re-usable; they peel off easily and dont leave any marks. Put them in your children s room, home for the holidays and seasons or office. The large pack is approximately 10.2 x .1 x 13.