Amazon.com: Max Water CTO 5 Micron, 10" x 2.5" Replacement Filter Cartridge, Coconut Shell Carbon Block for Whole House Water Filtration System and Standard RO (Reverse Osmosis) Filters - Pack of 25 :
Instapure IR20 Compatible Made in USA Whole House Filter, Reduces Chlorine, Taste, and Odor. Instapure ESSENTIALS DI-CTO-10-2.5 filter fits WaterPik® InstaPure IR-20, IR20, IF20, IF-20, IF20A, IF-20A, K-50. Designed to fit in
0.5 micron Coconut Shell CTO, Cyst Carbon Block Water Filter Cartridge – Blue Gold For Life Inc