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Watts F500398

Reverse osmosis system

Watts F500398 3-Stage RO Replacement Filters

This Watts 3-stage system, model F500398, is a traditional RO unit with innovative half-turn filter housings. The system is designed for undersink use and has industry standard cartridges. See below for all replacement filters and parts.

See the replacement schedule

Compatible parts

Everything that fits the Watts F500398

Omnipure OMB934-5m 5-micron carbon block filter for standard 10-inch water filter housings
Omnipure
Omnipure OMB934-5m Carbon Block Filter 5 Micron 2.5" x 10"
(83)
$14.99
Reduces chlorine, taste and odor
NSF Certified performance
USA made compression molded
2.5" Drop-in carbon block element
AXEON TF - 1812 - 50 Reverse Osmosis Membrane 50 GPD 200359 200359 - ESP Water
AXEON
AXEON TF-1812-50 Reverse Osmosis Membrane 50 GPD 200359
(10)
$44.49
Thin Film Composite (TFC)

Replacement filter info

Your replacement schedule

Each stage of the Watts F500398, the exact part that fits it, and when to change it.

  1. Stage 1: Carbon block filter

    Part OMB934-5m, Omnipure OMB934-5m Carbon Block Filter 5 Micron 2.5" x 10" $14.99

    Every 6–12 months

  2. Stage 2: RO membrane

    Part 200359, AXEON TF-1812-50 Reverse Osmosis Membrane 50 GPD 200359 $44.49

    Every 2 years

  3. Stage 3: Carbon block filter

    Part OMB934-5m, Omnipure OMB934-5m Carbon Block Filter 5 Micron 2.5" x 10" $14.99

    Every 6–12 months

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