Description This set of simple and practical air stones are made of high- quality silicon carbide material for durable and long term use. It is designed to add oxygen to your hydroponic growing system or aquarium. Suitable for ponds, aquariums, fish tanks and other systems. Features Color: Assorted Color. Material: silicon carbide. Size: About 10. 00X5. 00X5. 00cm 3. 93X1. 97X1. 97inch.- Sturdy and durable, great for home, office fish tank, aquarium and hydroponics tank.- The surface is delicate, fine polishing and smooth, and the bubble output is more even.- Use reliable and durable silicon carbide material, not easy to damage.- Add beauty to your display aquarium with these air stones to create micro bubbles.- Produce fine bubbles for oxygen replacement and lowering carbon dioxide levels. Package Including 2pcs x fish tank increasing oxygen air stones