This set includes all five filter stages that require replacement*. The set comprises:
1st Stage - 5 Micron Sediment Filter 20”
2nd Stage - Granular Activated Carbon Filter 20”
3rd Stage - Carbon Block Filter 20”
4th Stage - 200GDP TFC Membrane
5th Stage - Post Carbon Filter
* Cartridge longevity and performance depend on water usage and level of contamination.