4-Stage, 50 GPD Reverse Osmosis Replacement Cartridge Kit with Filmtec Membrane


In Stock as of 6:00pm EST


ROK-4M-50BST contains the highest quality replacement filters available for a 4-Stage, 50 GPD Reverse Osmosis System. Pentek is the largest brand in the industry, and Filmtec membranes have the highest contaminant rejection rates. All cartridges in this kit are NSF Certified.

This kit includes the following standard size replacement cartridges for a 4-Stage, 50 GPD Reverse Osmosis System like the one shown below.

Dow/Filmtec is the best performing Membrane available.

  • Industries leading brand of Reverse Osmosis Membrane
  • Highest Removal Rates
  • Made in the USA
4-Stage Reverse Osmosis System

4-Stage Reverse Osmosis System

Additional information

Gallons Per Day


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