The silicone JOESKI™ Shower Coffee Holder securely grips to glossy surfaces like glass, mirror, marble, metal, shiny tiles, and laminate using a patented technology. No suction cups, adhesives or wall mounts are needed, and it won't leave any residue behind. PLEASE NOTE: This product is not intended for use on stone and other unglazed tiles. Grip works best on smooth, glass-like surfaces. Do not use with glass bottles.