Give your Bestway pool its best performance by using the Bestway Filter Cartridge Type III/A. It is recommended you change the filter regularly so you can filter the water in your pool and keep it attractive and refreshing all season. Comes with 3 pool filter cartridges. This replacement cartridge works for your Flow Clear 530, 800, 1,300, or 1,500 gallon per hour filter pump. The model number for this replacement filter cartridge is 58012E. You can use it with any pool filter that needs a Type III or Type A filter cartridge that measures 4.2 inches in diameter and 8 inches tall. Ensure the long life of your Bestway pool and filter pump by replacing the filter regularly. For best performance, you should replace your pool filter cartridges once every 2 weeks.