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IsoTwist® – Premium RO System

IsoTwist ISO-550R 5-stage certified RO system

IsoTwist ISO-450R 4-stage certified RO system


5-Micron Polyspun Sediment Filter
Encapsulated 1/4 turn Twist-Off Cartridge
STAGE TWO (optional)
10 Micron Granular Activated Carbon Filter
Encapsulated 1/4 turn Twist-Off Cartridge
10 Micron Carbon Block Filter
Encapsulated 1/4 turn Twist-Off Cartridge
Reverse Osmosis Membrane
50 GPD TFC @ 65 PSI Pressure Differential
10 Micron Carbon Block Post Filter
Encapsulated 1/4 turn Twist-Off Cartridge
4.0 Gallon Plastic Tank (metal tank available)
Pre-pressurized with Butyl Bladder
(2.5 gal. water capacity when full)

Shipping Weight: 24 lb.
14”W x 6”D x 15.5”H
Tank: 11″ dia. x 15.5″H

Conditions of Use
Water Must be microbiologically safe
Temperature, 40 -100 degrees F
pH Range, 3 to 10
Feed pressure, 40 to 100 psig
Maximum TDS, 1500 PPM
Turbidity, less than 1.0 NTU

Certified Reduced Contaminants

Arsenic, Barium, Cadmium, Chromium III & VI, Copper, Fluoride, Lead, Radium 226 & 228, Selenium, TDS, Turbidity, Tested for structural integrity, chemical extraction and reduction of contaminants

Platinum Seal Certified 4 & 5-Stage RO with proprietary twist-off filters

The Vertex IsoTwist is our most advanced undersink Reverse Osmosis filter system optimized to treat city water using the existing water pressure. This model makes up to 50 gallons a day of great tasting water while taking up less space than most other 4 and 5-stage models. The higher production capacity serves larger homes and offices. The easy twist-off disposable filter cartridges and RO membrane assembly are designed to make installation and replacement quick, easy and sanitary. These sturdy and reliable US made systems are IAPMO Platinum Seal certified to significantly reduce 13 contaminants to NSF/ANSI 58 (see list below).

Choose the 5-stage system to ensure water quality, membrane performance and filter life, when the incoming water contains a high amount of sediment as in some well water systems. An extra pre-filter stage is added before the membrane. The 5-stage model can also be used to extend time between filter changes.

The IsoTwist comes complete and ready to install, with quick connect fittings, 3/8″ tank to faucet tubing, dispensing faucet and instruction manual.

Download the Brochure.

• Proprietary twist-off filter cartridges
• Hi capacity 50 GPD TFC RO membrane assembly for easy replacement
• Quick connect O-ring seal fittings
• Compact size takes less space than most 4 and 5-stage systems
• Auto shutoff valve
• Flow restrictor – modified capillary
• Long reach, non-airgap chrome faucet included
• 4.0 gallon plastic tank
• Feed water connector-1/2 inch threaded inlet adapter with metal ballvalve
• Drain connection included
• 1/4 Inch John Guest polyethylene tubing

IsoTwist Ordering InformationPart No.
5-stage Reverse Osmosis SystemIso-550R
4-stage Reverse Osmosis SystemIso-450R
Available Options
with UV Sterilizer add /UV
with Air Gap Faucet (meets many city's requirements)add /AG
with Metal Tankadd /MT
with Quick-Connect fittings (includes 3/8" line from tank to faucet)add /QC
with 3/8" Feed Water Adapteradd /3/8FWA
with 1/2"-3/8" John Guest Convertible Feed Water Adaptercall factory
Replacement Filters
5 micron sediment 1/4 turn Twist-On cartridgeTF-4113
Carbon Block 1/4 turn Twist-On cartridge (2 per)TF-4115
GAC 1/4 turn Twist-On cartridge (for 5-stage option)TF-4114
50 GPD RO membrane assembly w/QC fittingsMHA-4222
50 GPD RO membrane onlyMA-4203
4-stage Filter Replacement Kit FK-112
5-stage Filter Replacement Kit FK-113
For Sales, Service or Parts, contact