​The Watts 10" replacement cartridge bundle includes all of the filters you need to keep your Watts W-315 50 GPD Certified Three-Stage Reverse Osmosis System working properly for a full year. The sediment pre-filter and carbon block post-filter should be changed every 6-12 months depending on usage and water quality. The reverse osmosis membrane should be replaced every 24 months.

The bundle includes:
    • Two 10” FPMB5-978 5 micron Sediment Pre-Filters    
    • One 10” W-1812-50 50 GPD RO Membrane
    • Two 10” F109009 5 micron Carbon Block Post-Filters

​​NOTE: Orders over $99.00 qualify for free shipping within the 48 contiguous United States.