Unicel C-5300 Spa Replacement Cartridge Filter 50 Sq Ft Jacuzzi Front Load PJW23 Industry's most complete line of replacement filter elements Clearwater Spas Florida Whirlpool Jacuzzi Whirlpool Bath (Note: 50 sq.ft. cartridge is an upgrade for P/N 6199000 (C 5601)) Seven Seas (Note: Product has closed top)