These powerful vacuum suction hooks feature the unique power inner thread lock design that creates maximum suction on smooth clean surfaces.could more than 22LB.great for hanging shower and bath accessories in a bathroom or kitchen utensils and tools on a tile backsplash.make from ABS plastics,rubber material;Metal hook length :4.7 CM; Suction Cup diameter:5.3 CM. <br> <br> Usage tips: <br> <br> 1. To ensure best performance,before installation need to fully clean both the suction cups and smooth surface. <br> 2. If the suction become deformation or harden up because of cold weather, soak in 50 degree hot water for 10 minutes first, dry up then push agaist the smooth surface. <br> 3. Firmly push the suction cup against a cleaned surface turn tri-wingnut clockwise until it will no longer rotate. Insert the steel hook in one of three holes. <br> 4. To release the suction seal, turn the tri-wingnut counter-clockwise and release. <br> 5. DO NOT suitable for surfaces such as cement, ceramic tile juncture,plasterer, metope paint, latex paint, wallpaper metope, archaize brick, ceramic tile of aging, tiles with slightly craze and dark grain.