uxcell Aquarium Fish Tank Plastic Air Line Tubing Holder 30mm Suction Cups Clear 6 Pcs Product Name : Aquarium Suction Cup;Color : Clear Material : Soft Plastic;Fit Tubing Max. Dia : 20mm/ 0.7" Cup Diameter : 30mm/1.2";Total Size : 30 x 30mm/ 1.2" x 1.2"(H*D) The suction cup part is made of soft plastic material, it will stay firmly on the surface of your fish tank or aquarium. Fit for airline or tube diameter 20mm, great for aquarium airline air tubing.