DescriptionThis professional Air Stone is made of sandstone materials,durable and practical, and has a long service life. This is a great wayto add oxygen to your aquarium, fish tank, hydroponics and circulatorysystem. Very suitable for use in fish tanks and aquariums. It will beyour good choice.Features-Color:Light Grey -Material:Sandstone -Size:4.00X4.00X1.50cm/1.57X1.57X0.59in -Durable, very suitable for home, office fish tanks, aquariums and hydroponic nutrient tanks.-Thesurface is fine and smooth, and the bubble output is more uniform. Theinstallation method is simple and easy to use, save your effort.- Air Stonecan be used for aquarium purification, filtration, water quality and oxygen aeration.-Itcan be washed repeatedly and undoubtedly can be used for a long time. Apractical and useful tool for your fish tank, help to create more airbubbles.-This air stone can produce tiny bubbles, increase oxygen content and circulate nutrients.