GelGems Window Clings: Mermaids with Dolphins and Sea Creatures, 3-Piece Gift Set Create an under-the-sea, marine fantasy world on a child's bedroom window or a glass shower door. Brightly colored and pleasantly squishy, translucent GelGems are a fun artistic medium that provides instant gratification to kids and grown-ups who love to express their creativity. Easily stick to and peel off any clean, dry, smooth, temperate, non-tinted glass surface such as windows, mirrors, glass dividers and more. Washable and re-usable, they peel off easily, leave no marks on glass, but are NOT recommended for use on painted, drywall or other porous surfaces. Non-toxic, safety tested and approved for ages 4+.