The 6-stage Reverse Osmosis water system replacement filter set for the Water General RO6100 includes:

(1) 5 micron sediment filter
(2) Carbon Block cartridges
(1) inline post carbon
(1) DI Resin filter

For maximum water quality, this set needs changed out once every 12 months.  

The replacement membrane for this model is not included as it should be changed every 4 years.