Summer Waves Polygroup Pool Filter Cartridge Replacement Size Type A or C 2 Pack The Summer Waves Polygroup Pool Filter Cartridge Replacement Size Type A or C 2 Pack is a high-quality product designed for easy installation in above ground pools. Made by the trusted brand Summer Waves, these filter cartridges are compatible with Summer Waves and Polygroup pools. With a height of 8 inches and a length of 4 inches, these cartridges are essential for maintaining clean and clear pool water. Suitable for use in both Type A and Type C filter systems, this 2 pack ensures you have spare cartridges on hand for when you need them.