SKU: 1525931116

4"x21" | 800 GPD | 99.6% Salt Rejection | Watermaker Seawater RO Membrane | Applied Membranes

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Description

4"x21" | 800 GPD | 99.6% Salt Rejection | Watermaker Seawater RO Membrane | Applied MembranesAMI 4x21 Seawater Desalination Reverse Osmosis Membranes For Watermakers and Land and Sea Based Seawater Desalinators Highest Salt Rejection Seawater RO Watermaker Membranes AMI high rejection and high productivity seawater reverse osmosis membranes are specially designed for marine applications. AMI SWRO membranes are ideal for seawater desalination in shipboard applications, watermakers, land based desalinators and sea based desalinators. AMI

AMI 4x21 Seawater Desalination Reverse Osmosis Membranes
For Watermakers and Land-and-Sea Based Seawater Desalinators


Highest Salt Rejection Seawater RO Watermaker Membranes

AMI high rejection and high productivity seawater reverse osmosis membranes are specially designed for marine applications. AMI SWRO membranes are ideal for seawater desalination in shipboard applications, watermakers, land-based desalinators and sea-based desalinators. AMI Membranes are 100% Quality and Performance Tested in their ISO 9001:2015 Certified Facilities.

Looking for a replacement seawater desalination membrane element for your watermaker filter system? View our Watermaker Replacement Membrane Chart.


Benefits of AMI Seawater Desalination RO Membranes:

  • Convert seawater into drinking water on yachts, boats, cruise ships, off-shore platforms, and resorts
  • High Rejection & Flow Rate
  • Manufactured in ISO 9001:2015 Certified Facilities
  • 100% Performance and Quality Tested
  • High Quality for Consistent and Reliable Performance
  • Uses the most advanced membrane film technology and manufacturing processes
  • Standard dimensions to fit in commonly available housings

M-S4021A Specifications

AMI Model Number M-4021A
Can Replace Models:



DOW SW30-4021
DuPont SW30-4021
FilmTec SW30-4021
Industry-Standard 4x21 Size Seawater RO Elements
Size (Approximate): 4" Dia. x 21"L
Flow Rate: 800 gpd (3.03 m³/d)
Applied Pressure: 800 psig (55 bar)
Stabilized Salt Rejection: 99.6%
Minimize Salt Rejection: 99.4%
Single Element Recovery: 4%
Exterior: Hard Shell Fiberglass
Membrane Type:
Polyamide Thin-Film
Composite

Permeate flow and salt rejection based on 32,000 ppm NaCl feed stream, pressure and recovery listed above. Element Permeate flow may vary +/- 20%

M-S4021A Operating Limits

Maximum Operating Temperature: 113°F (45°C)
Maximum Operating Pressure: 1,000 psig (69 bar)
Maximum Pressure Drop: 15 psig (1 bar)
Maximum Feed Flow Rate: 16 gpm (3.6³/h)
pH Range, Continuous Operation: 2-11
pH Range, Short-Term Cleaning: 1-13
Maximum Feed Silt Density Index: SDI 5
Fere Clorine Tolerance: 0


Related Products for use with M-S4021A Seawater Elements

C-C2510-A11 Membrane Cleaning Cartridge with Acid Cleaner to Remove Scale Buildup and Prolong Membrane Life
C-C2510-A22 Membrane Cleaning Cartridge with Alkaline Cleaner to Remove Organics and Prolong Membrane Life
C-C2510-A88 Membrane Preservative Cartridge for Preserving the System and Membrane During Extended Periods of Non-Operation.
655139-03 Oil Absorbing Filter Cartridge - Oil-Water Separator Replacement Cartridge, 20" Big Blue Pentair Pentek Filter
H-F10100CF Plankton Filter - 10" Standard 100 Micron Spun Polypropylene Replacement Filter Cartridge

Common Applications for AMI Seawater Watermaker Elements:

  • Seawater Desalination
  • Marine Applications
  • Watermaker RO Systems
  • Yachts

Physical Dimensions of AMI M-S4021A SWRO Marine Element

INCHES (MM)
L 21 (533)
I 19 (480)
D 3.9 (99)
P 0.75 (19)
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 1525931116

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4.5 ★★★★★
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Verified Purchase
Chrissy.
West Palm Beach, US
★★★★★ 1
Bitter Taste
The packing is well done, the look is presentable but the taste.. it’s not anything close to home. Or Rather the two countries who make Biltong/Droëwors. It has a bitter taste and I sadly won’t be ordering again. I was hoping it’s something I would be ordering multiple times. But that’s not happening.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on September 12, 2025
E
Verified Purchase
Everything great. Delivered with care. Thank you much.
Houston, US
★★★★★ 5
Iam South African living in USA. Its great that i found wors
Real wors. Thank you
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Reviewed in the United States on May 26, 2026
J
Verified Purchase
Justin meglich
San Leandro, US
★★★★★ 2
Meh
Good flavor, too dry and crumbly
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 20, 2026
H
Verified Purchase
Heinrich Schoeman
Birmingham, US
★★★★★ 5
Great chicken spice
Love this south african spice.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 15, 2025
M
Verified Purchase
Mirella Res
Port Orchard, US
★★★★★ 5
Best tasting spice!
Best chicken spice ever! I used on roasted potatoes and beef as well! I always have a bock in my pantry!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 18, 2026

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