Meifrenship Upgraded Pool Unit 7.5K-20K Gallons for up to 6 Months Blue

["Crystal Clear: With this pool cartridge replaced, you can actually see and feel the difference in the quality of water, let's welcome a christal clear pleasant pool experience back into our home.","Fits Most Pool Capacities: Holding up to 7,500 to 20,000 gallons of water.","6-Months Hassle-Free Protection: It is recommended to replace the cartridge every six months to improve efficiency. For optimal performance, start fresh with this cartridge at the beginning of each swim season."]