SKU: 69581433787

4" x 21" | 900 GPD Commercial Reverse Osmosis RO Membrane | Applied Membranes

$166.70 $185.22
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Description

4" x 21" | 900 GPD Commercial Reverse Osmosis RO Membrane | Applied Membranes4" x 21" Reverse Osmosis Membrane Tap or Brackish Water 900 GPD RO Membrane AMI commercial RO membrane elements produce high quality water from tap or brackish water in small commercial RO systems, and are among the finest in the industry. With hundreds of thousands of membranes in operation in water filtration systems world wide, AMI membranes have earned a reputation of delivering consistent, reliable, and long lasting performance, making AMI


4" x 21" Reverse Osmosis Membrane | Tap or Brackish Water | 900 GPD RO Membrane

AMI commercial RO membrane elements produce high quality water from tap or brackish water in small commercial RO systems, and are among the finest in the industry. With hundreds of thousands of membranes in operation in water filtration systems world-wide, AMI membranes have earned a reputation of delivering consistent, reliable, and long lasting performance, making AMI Membranes the natural choice for use in small commercial RO systems. AMI Small Commercial RO Membranes are constructed of tap water TFC (thin film composite) membrane material and fit standard PVC and Stainless Steel RO Membrane Housings.

AMI Membranes are 100% Quality and Performance Tested in their ISO 9001:2015 Certified Facilities.

Specifications for M-T4021A

AMI Part Number: M-T4021A
Membrane Size (Nominal): 4 x 21
Membrane Dimensions: 3.9"Dia. x 21"L
Flow Rate: 900 GPD (3,407 LPD)
Applied Pressure: 225 psi (1.6 MPa)
Stabilized Salt Rejection: 99.5%
For Housing: Standard 4" x 21"
Outer Wrap: Tape Wrapped
Membrane Type: Tap or Brackish Water
Membrane Sheet: TFC (Thin Film Composite)
Element Type: Spiral Wound
Feed Water Test Temperature: 77°F (25°C)
Single Element Recovery: 8%
Chlorine Tolerance: 0
Feed water pH Range: 2-11
Can Replace:




 DOW FilmTec TW30-4021
DuPont TW30-4021 80608
GE Desal AG4021TM
GE Desal AG4021TF
Axeon HR3-4021
Manufacturer: Applied Membranes, Inc.
Country of Manufacture: United States (USA)

Note: Performance specifications based on 2,000 mg/l sodium chloride, 225 psi (1.6 MPa) applied pressure, 77ºF (25ºC) feed water temperature, pH 8 and the recovery listed in the table above. Element permeate flow may vary ± 20%.

Features of AMI Tap Water / Brackish Water RO Membranes

  • High Rejection & Flow Rate
  • Manufactured in our ISO 9001:2015 Certified Facilities
  • 100% Performance and Quality Tested
  • Backed by our Experienced Technical Support Staff
  • 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

Applications for AMI Commercial RO Membranes

  • Restaurants
  • Aquariums
  • Whole House (Residential)
  • Office
  • Institutions
  • Hotels
  • Hospitals
  • Disaster Relief
  • Spot Free Rinse/Car Wash
  • Labs
  • Pharmaceutical
  • Humidification
  • Misting
  • Manufacturing
  • Rinse Water
  • Bottled Water
  • Water stores
  • Beverage
  • Food Processing
  • Ice Makers
  • Commercial Water Treatment
  • Ice Makers
  • Tap Water
  • Brackish Water
  • Wide Variety of Other Applications

Physical Dimensions of M-T4021A:

Total Length (L):

21 In. (53.3 cm)

Membrane Length (I):

19 In. (48 cm)

Diameter (D):

3.9 In. (9.9 cm)

PWT (P):

0.75 In. (1.9 cm)

Replacement Compatibility for AMI 4 X 21 RO MEMBRANES

Applied Membranes M-T4021A membrane elements can be used as direct replacement for many industry-standard 4x21 size RO elements with 3/4" male product water tubes ("stinger style") which are rated at 225psi. These include DuPont DOW FilmTec TW30-4021 (80608), GE Desal AG4021TM (1206750, AG4021TF), and Axeon HR3-4021.

If you do not see your membrane listed or wish to learn more about compatibility, please contact us. Our certified water treatment experts will be happy to discuss your application. To ensure prompt and accurate information, please include as much information about your system as possible, such as: model, manufacturer, model of membranes being replaced, any available. product manuals or literature associated with your system, and photographs of your system or membranes.

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: 69581433787

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4.5 ★★★★★
Based on 25 reviews
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Product Reviews
A
Amazon Customer
Natrona Heights, US
★★★★★ 5
Great boys slim fit suit for weddings, church, or special events
Color: Medium Grey, Size: 12
Great kids suit. Comes with a jacket, pants, and tie. Does not have a shirt. Fits as expected. Classic cut on the lapels. Great quality materials. Well made pants and jacket. The color is consistent without any fade or dark spots that can happen with lower quality fabrics. Looks great on. My son loves it. Says it is not restrictive, he can move easily in it. Highly recommend for church, special events, weddings, etc.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 22, 2025
M
Mommynificent
Natrona Heights, US
★★★★★ 5
Nice high-quality, light weight suit for a tween!
Color: Navy Blue, Size: 10
This is such an attractive suit for a tween boy! My son loves dressing up, and this is his new favorite suit. He really likes the double-breasted style and the light weight of the fabric so that it isn't too hot. The tie that came with it gives major Harry Potter vibes which we weren't expecting, but he has lots of other ties that he also enjoys pairing with it. The size seems right, and it fits him well. He says it is very comfortable. I'm happy with the quality and the navy color.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 14, 2025
A
A. Beauto
Pawtucket, US
★★★★★ 5
Stylish and great value!
Color: Medium Grey, Size: 14
This grey suit was a great find for a school ceremony and will definitely be used again. The neutral color makes it easy to pair with different shirts and ties, and it has a modern, clean-cut look. The jacket and pants fit nicely after a quick press, and the quality was better than I expected for the price. It lost a star only because the waist on the pants needed a slight adjustment, but overall, we’re very happy with it!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 10, 2025
N
N. Hale
Battle Creek, US
★★★★★ 3
Runs big, and fabric may not be same color as picture
Color: Medium Grey, Size: 16, Color: Medium Grey, Size: 16
This suit was a good find for us, as we usually dress up for church, and my 13 yo son often wears suits. He normally wears a size 16, so that’s what we ordered, and in dark charcoal gray. The suit we got was a light, heathered gray that didn’t look much like the one in the picture. It was very wrinkly and thin, and a little scratchy. Also, the sleeves were way too long and the torso cut of the jacket was pretty wide. The pants were very large in the waist, but fit him decently in the length (he’s 5’4” and weighs 90 lbs). Overall the suit looked like it was drowning him, so I would order a size down unless you have a larger child/teen. Because of the ill fit, I haven’t had the chance to see what the suit looks like on him as it’s supposed to, but I guess I’ll return it or wait a year or two until he fills it out a bit more. Not overly impressed with the quality, so I’m not sure I’d pay $55 for this one again.
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Reviewed in the United States on October 20, 2025
A
Amy
Birmingham, US
★★★★★ 5
Adorable, Complete Set—Great for Special Occasions
Color: Beige, Size: 12, Color: Beige, Size: 12
This suit set is such a great find! It comes with everything you need—jacket, pants, shirt, tie, and bow tie—which makes getting a dressed-up look so easy. It's excellent quality for a suit in this price range. The linen fabric gives it a nice, lightweight feel and a polished look that works well for both formal and semi-casual events. My son looked adorable in it, and it was perfect for the spring wedding we attended. What I love: Complete 5-piece set—no need to buy extras Lightweight and comfortable material Classic, stylish look with nice details (lapel, pockets, etc.) Adjustable waistband is super helpful for fit Versatile for weddings, holidays, and other events Fit was true to size based on the chart, but I agree with the recommendation—if your child is between sizes or growing quickly, sizing up is a good idea. I sized up with the hopes that he can wear it again for another event because it looks fantastic! Overall, a really cute and practical suit set that looks great without being uncomfortable. Perfect for any special event
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 22, 2026

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