The Air Stone is designed to gradually diffuse the air into the water tank and provide oxygen for the fish to breathe. If you are a fan of aquatic animals, the surroundings of your house are essential. Our air stones are made of high-class materials and are durable. Features -Color:Assorted Color -Material:Sand, plastic -Size:4.80X1.50X1.50cm/1.89X0.59X0.59in -Note:Suitable for hose with inner diameter of 4mm. -The small and dense bubbles produced stones can not only provide oxygen for fish but create beautiful and lovely bubbles scenes under water. -It can repeatedly diffuse fine and uniform bubbles, with rapid aeration. You can send it as a present for your friends who raise fish, give them a little . -Designed to add oxygen and circulate nutrition to your hydroponic growing system. Great for freshwater, saltwater and hydroponic use. -It produces fine bubbles making it efficient in the replacement of oxygen in fish ponds, tanks or hydroponic systems. -A great way to properly aerate a home aquarium. It creates a circle of bubbles that helps keep healthy fish and adds to the beauty of the aquarium. Package list: 5 x stone 5 x white air stone