1、The aerobic filter cotton has good physical filtration and biochemical filtration, and under the 630g encryption structure, there are also conditions for rapid microbial implantation and growth. 2、Using 630g high‑density fiber, it has better cultivating ability than the 500g density cotton on the market, and its filterability is improved by 30%. 3、It is flexible and resistant to washing and rubbing; it is not easy to deform and can be used for a long time and customized. 4、Multiple filtration effects to achieve better filtration and larger microbial cultivation area under the same volume. 5、The mesh distribution filter, the flow resistance is small, and the filtering effect is high. 6、It has a wide range of applications. Various types of fish tanks, fresh water or sea water are suitable for use. 1Bag x Filter Cotton Item Type: Cotton Filter PadMaterial: Fiber CottonProduct Size:Length: Approx. 99cm / 39inWidth: Approx. 13cm / 5.1inWeight: Approx. 80g / 2.8oz Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.