Four cartridges
Stages 1, 2, 4, and 5
Includes the sediment prefilter, T28 coconut carbon prefilter, mixed-bed DI cartridge, and T33 coconut carbon post-filter.
4-Filter Replacement Set for 5-Stage UltraPure Countertop RO Systems — Sediment, T28, DI & T33 with 8 Fittings — SKU 4FILTER1
Price range: $49.00 through $119.00
4 Filter Set for 5-stage Universal Countertop RO Systems, including 5m Sediment, T28, DI and T33 inline filter cartridges, SKU# 4FILTER1
- Description
- Additional information
- Reviews (1)
Description
4-filter maintenance set for 5-stage UltraPure countertop RO
Sediment, T28 carbon, mixed-bed DI, and T33 post-carbon cartridges with eight replacement fittings
This maintenance set is designed for compatible 5-stage UltraPure portable and countertop reverse-osmosis systems using inline quick-connect filters. It replaces the four non-membrane filtration cartridges and includes eight replacement fittings for renewing the inlet and outlet connections during service.
4 filtersAll non-membrane cartridges
8 fittingsReplacement connections included
10″ × 2″Inline cartridge format
No membraneRO membrane sold separately
Routine system maintenance
Replace the sediment, carbon, and DI stages without changing the RO membrane
This set is intended for the regular service interval when the four inline cartridges need replacement but the existing RO membrane is still producing the required rejection. Replacing the complete non-membrane set helps restore flow, chlorine pretreatment, membrane protection, ionic polishing, and final taste performance.
Service hardware
Eight Replacement Fittings
Includes two replacement fittings for each inline cartridge, allowing the inlet and outlet connections to be renewed during installation.
Four replacement filters
Particle protection, carbon pretreatment, DI polishing, and final taste treatment
1
5-Micron Sediment Filter
Helps capture rust, sand, dirt, and suspended particles before they reach the carbon filter and RO membrane.
2
T28 Coconut Carbon Filter
Helps reduce chlorine, taste, odor, and selected organic compounds while helping protect the RO membrane.
4
Omnipure K2555-BB DI Filter
Mixed-bed ion-exchange media further polishes residual dissolved ions that pass through the RO membrane.
5
T33 Coconut Carbon Filter
Provides final taste and odor polishing before the water is collected for use.
Package contents
Filters and replacement fittings included
- ✓1 × 5-micron inline sediment filter
- ✓1 × T28 coconut-shell activated carbon prefilter
- ✓1 × Omnipure K2555-BB mixed-bed DI filter
- ✓1 × T33 coconut-shell activated carbon post-filter
- ✓8 × replacement fittings
Key benefits
A complete non-membrane service set for the 5-stage UltraPure system
Four Matching Filters
Replaces all non-membrane cartridges in a compatible five-stage UltraPure countertop RO system.
Sediment Protection
Helps protect the carbon stage and RO membrane from suspended particles.
Chlorine Pretreatment
The T28 carbon stage helps reduce chlorine before water reaches the membrane.
Mixed-Bed DI Polishing
Further reduces residual ions after reverse osmosis.
Eight New Fittings
Provides replacement inlet and outlet fittings for all four cartridges.
Inline Quick-Connect Format
Designed for compatible classic countertop systems using 1/4″ tubing connections.
Specifications
Verified cartridge details
| Product type | Four-filter maintenance set for 5-stage UltraPure countertop RO systems |
|---|---|
| Compatible system type | Selected portable and countertop RO systems using sediment, T28, RO membrane, DI, and T33 stages |
| Sediment filter | 5 micron, approximately 10″ × 2″, 1/4″ female ports |
| Sediment manufacturer SKU | IL-10W-S514 |
| Carbon prefilter | T28 coconut-shell activated carbon, approximately 10″ × 2″, 1/4″ female ports |
| T28 manufacturer SKU | CL10ROT28-B |
| DI filter | Omnipure K2555-BB mixed-bed ion-exchange filter, approximately 10″ × 2″, 1/4″ female ports |
| Post-carbon filter | T33 acid-washed coconut-shell carbon, approximately 10″ × 2″, 1/4″ female ports |
| T33 manufacturer SKU | IL-10W-C |
| Replacement fittings | 8 pieces included |
| Filter quantity | 4 cartridges total |
| RO membrane | Not included |
| Listed package dimensions | 10 × 10 × 2 in |
| Listed package weight | 56 oz / 3.5 lb |
| Primary SKU | 4FILTER1 |
| Compatible SKUs | 4FILTER, 4FILTER1, and 4FILTER2 |
Typical replacement schedule
- ✓Sediment filter: replace based on flow, discoloration, sediment load, or the system schedule
- ✓T28 carbon filter: approximately 8–12 months or up to 1,500 gallons, depending on water quality and usage
- ✓DI cartridge: approximately 8–12 months or when post-DI TDS rises beyond the required target
- ✓T33 carbon filter: approximately 8–12 months or up to 1,500 gallons, depending on water quality and usage
- ✓RO membrane: inspect separately and replace based on age and measured rejection
Compatibility checklist
Confirm the existing system before ordering
✓
Five-stage UltraPure configuration
The system should use sediment, T28 carbon, RO membrane, mixed-bed DI, and T33 post-carbon stages.
The system should use sediment, T28 carbon, RO membrane, mixed-bed DI, and T33 post-carbon stages.
✓
Inline 1/4″ tubing connections
Confirm that the existing cartridges use compatible 1/4″ tubing and removable fittings.
Confirm that the existing cartridges use compatible 1/4″ tubing and removable fittings.
✓
Existing membrane still performs properly
This maintenance set does not include a replacement RO membrane.
This maintenance set does not include a replacement RO membrane.
✓
Correct stage order
Install each cartridge according to its flow arrow and original position in the system.
Install each cartridge according to its flow arrow and original position in the system.
Replacement guidance
Plan approximately 30–40 minutes for the filter change
1
Shut Off and Depressurize
Disconnect the system from the faucet and allow pressure to dissipate before removing tubing or fittings.
2
Record the Tube Routing
Photograph and label each tube before disconnecting the old cartridges.
3
Replace One Filter at a Time
Match each flow arrow and stage position, then install the supplied replacement fittings.
4
Flush and Check for Leaks
Pressurize slowly, inspect every connection, and flush the new filters before using the water.
Before purchase
Good to know
!
RO membrane is not included
This set replaces the four non-membrane filters only.
This set replaces the four non-membrane filters only.
!
Wrench is not included
A membrane-housing wrench is unnecessary for this cartridge-only maintenance set.
A membrane-housing wrench is unnecessary for this cartridge-only maintenance set.
!
Monitor DI exhaustion
Replace the DI cartridge when post-DI TDS rises beyond the target required for the application.
Replace the DI cartridge when post-DI TDS rises beyond the target required for the application.
!
Universal does not mean every system
Filter size, port type, tubing size, and stage sequence must all be compatible.
Filter size, port type, tubing size, and stage sequence must all be compatible.
!
Flush before use
New carbon and DI filters require thorough flushing before taste and TDS readings stabilize.
New carbon and DI filters require thorough flushing before taste and TDS readings stabilize.
!
Photo must show all included parts
The updated product image should display all four cartridges and all eight replacement fittings.
The updated product image should display all four cartridges and all eight replacement fittings.
This product includes four replacement filter cartridges and eight replacement fittings. It does not include an RO membrane, membrane housing, wrench, frame, clips, tubing set, faucet adapter, or flow restrictor.
Not sure whether this set matches your UltraPure countertop RO system?
Send the system model, filter labels, tubing size, post-RO TDS, and clear photos of the existing assembly before ordering.
Send the system model, filter labels, tubing size, post-RO TDS, and clear photos of the existing assembly before ordering.
Additional information
| Weight | 56 oz |
|---|---|
| Dimensions | 10 × 10 × 2 in |
| Choose | Assembly, Filter Set |
1 review for 4-Filter Replacement Set for 5-Stage UltraPure Countertop RO Systems — Sediment, T28, DI & T33 with 8 Fittings — SKU 4FILTER1
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David –
These filters work great!