Material: Nloy Size: 15*20cm Package Included: 10*Aquarium Filter Media Bags 1.The nylon mesh bags won't tear open, safe, durable, washable and reusable.Zipper design to simplified operation, easy to fill and empty, keep the filter media safe. 2.Suitable for pelletized carbon, respiratory biological rings,activated carbon, volcanic rocks, coral sands, ceramic rings, etc. 3.Durable material: the media filter bag is made of corrosion-resistant polyester material, the mesh will not be blocked by air bubbles, improving the water quality and filter media usage time and efficiency. 4.Thoughtful design our plastic zipper is more safety for media filter, reusable and great for long time use, differ to the metal one which may easily get rust and pollute your water. 5.Function: place the mesh bag containing the filter media in the aquarium to keep the aquarium clean and clean. Suitable canister filters, power filters, wet/ dry filters, swimming pool and pond.