Intex 28633EG Krystal Clear Cartridge Filter Pump for Above Ground Pools, 2500 GPH Pump Flow Rate, 110-120V with GFCI Easy to use - simply replace the old cartridge with a new one every two weeks Double insulated pump Air release valve for air trapped inside filter chamber Sediment flush falve at bottom of filter chamber Works with 18-feet Easy Set, 18-feet Metal Frame, or 18-feet by 10-feet Oval Frame pools