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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4.9 ★★★★★
Based on 12 reviews
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Product Reviews
M
Verified Purchase
Mike B
Grantham, US
★★★★★ 5
Maybe the best glove in golf! Wife loves the glove!
Color: White, Size: Medium-Large, Style: WeatherSof Prior Generation, Configuration: Worn on Left Hand
My wife loves her glove! Comfortable, fits well and is pretty durable in the short term use. Time will tell if it’s durability is long term or not.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 29, 2025
I
Verified Purchase
Indy Customer
San Leandro, US
★★★★★ 5
Part of Your Skin
Color: White, Size: Large, Style: WeatherSof Prior Generation, Configuration: Worn on Left Hand
Golf clubs are worn to steady your grip, keep the grip clean and most of all--keep the club from flying out of your hand. This glove does the trick and even after 18 holes feels invisible--like part of your skin. It is snug but not constricting. The glove is part mesh and has strategic cutouts so that it breathes. I golf for fun and bought this at the suggestion of a very fine golfing friend. It is well made for a good price.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 20, 2024
J
Verified Purchase
Junk! Falling apart. Don’t buy this crap
Draper, US
★★★★★ 5
Quality/value ratio is high.
Color: White, Size: Large, Style: WeatherSof Prior Generation, Configuration: Worn on Left Hand
Great quality and fit. Bought 2 more since they are a great value.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on July 30, 2025
M
Verified Purchase
MakennaB
Natrona Heights, US
★★★★★ 4
Runs small
Color: White, Size: Small, Style: WeatherSof Prior Generation, Configuration: Worn on Left Hand
This is an amazing product, but it does run a little small
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on July 17, 2024
S
Verified Purchase
SanjoBanjo
Pawtucket, US
★★★★★ 5
Women's Golf Glove
Color: White, Size: Medium, Style: WeatherSof Prior Generation, Configuration: Worn on Left Hand
Love the classic fit. Some other brands may need to be medium-large, but this medium works well Wore it yesterday. Good grip. Removed glove on each hole before getting on the green. Our current weather is hot and humid. Still fairly easy to remove glove! Soft and lightweight. Worn on my left hand. For weekly use in league play. Would recommend. Also like the extra pad on heel of your hand. Plan to only wash by hand In woollite and drip dry. Wish it came in pink, but bright white looks fine. Price is comparable to other brands i have purchased.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on September 24, 2024

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