Unicel C-4325 Compatible Hot Tub Spa Filter - $14.13
SpiroPure Replacement for Pleatco PA225 Unicel C-4325 Filbur FC-1220 Hayward CX225RE Micro Star Clear C225 Hot Tub Spa Pool Filter Replacement Cartridge (Case of 6) - Walmart.com
Unicel C-4313 Filter Cartridge – Pool Geek
Amazon.com : Cryspool Pool Filter Compatible with CX225RE, C225, Commander II 57010500, PA225-4/M4, Unicel C-4325, FC-1220,25 sq. ft., 2 Pack : Patio, Lawn & Garden