Sanwood Reusable Super Powerful Vacuum Towel/Key Suction Cup Hook Holder - Strong Hooks for Bathroom & Kitchen (One Hook) Material: ABS + Chrome-plated Metal, PVC Hook Length: 60mm/ 2.36" (Approx.) Suction Cup Diameter: 55mm/ 2.16" (Approx.) EASY TWIST & FIX - It is very convenient to rent an apartment, people move frequently. Simply loosen the suction cup and take a hook. Within a few minutes, place in a new location. Suction works best on clean ceramic tile, glass, mirror, granite, stainless steel, acrylic, laminate and any non-porous surface with glossy finishSuction works best on clean ceramic tile, glass, mirror, granite, stainless steel, acrylic, laminate and any non-porous surface with glossy finish Suction will NOT work on stone, wood, sanded tile, porcelain, marble, dry wall & any surface that is bumpy, porous or matte finished