SKU: 97980762221

4"Dia.x21"L PVC Membrane Housing

$188.03 $208.92
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Ships within 48 hours · Estimated delivery Aug 20 - Aug 25

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Description

4"Dia.x21"L PVC Membrane Housing4 x 21 PVC Membrane Housing Pressure Vessel for RO Membranes AMI PVC pressure vessels for housing 4" x 21" membrane elements are ideal for lower pressure membrane applications up to 200 PSI are designed for direct connection to AMI Applied Membranes and FILMTEC DOW style elements. The U Pin style end closures are designed for ease of installing and replacing membrane elements, and the " FNPT connections for ease of connection with no special fittings


4 x 21 PVC Membrane Housing Pressure Vessel for RO Membranes

AMI PVC pressure vessels for housing 4" x 21" membrane elements are ideal for lower pressure membrane applications up to 200 PSI are designed for direct connection to AMI/Applied Membranes and FILMTEC/DOW style elements. The U-Pin style end closures are designed for ease of installing and replacing membrane elements, and the ½" FNPT connections for ease of connection with no special fittings required. Each membrane housing is individually inspected for quality assurance.

Each membrane housing is sold complete with End Plugs, U-Pins, Feed Plugs, and O-Rings. Mounting pads and straps are sold separately.

PVC Membrane Housing Specifications

AMI Part Number: PV4021PWG
For Membrane Size: 4" x 21"
For Membrane Type: AMI/Applied Membranes, DOW/FilmTec Style
Operating Pressure: 200 PSI (14 BAR) at 77°F (25°C) Maximum
Vessel Dimensions: 4" Dia. x 25.75" Length
(10 cm Dia. x 65.4cm Length)
Connections: ½" FNPT Feed, Brine, and Product
Configuration: End Entry
End Closures: U-Pin
Materials: NSF approved Rigid PVC, PVC end plugs, PVC reinforcement cuffs and stainless steel cuff bands

Warning: 4x21 PVC pressure vessels are limited to a maximum pressure of 200 psi (14 BAR) at 77°F (25°C). Higher pressure, higher temperature or water hammer will lead to premature failure. It is highly recommended that when these conditions exist, a pressure switch or relief valve be installed to protect the vessel. Alternatively, you may consider a stainless steel or FRP vessel.

Replacement Components for 4x21 PVC Housings

{{widget type="Magento\Catalog\Block\Product\Widget\Link" anchor_text="PV4040PD1212" title="Replacement End Plug for 4-Inch Membrane Housing Pressure Vessel" template="product/widget/link/link_inline.phtml" id_path="product/229"}} End Plug with ½" Brine x ½" Product Ports, with O-Rings
{{widget type="Magento\Catalog\Block\Product\Widget\Link" anchor_text="PV-RR40U" title="Replacement U-Pin for 4-Inch Membrane Housing PVC or SS" template="product/widget/link/link_inline.phtml" id_path="product/230"}} U-Pin
{{widget type="Magento\Catalog\Block\Product\Widget\Link" anchor_text="PV-OR40-342" title="Replacement O-Ring for 4-Inch Membrane Housing Pressure Vessel SS or PVC" template="product/widget/link/link_inline.phtml" id_path="product/231"}} O-Ring for End Plug - External
{{widget type="Magento\Catalog\Block\Product\Widget\Link" anchor_text="PV-OR40-210" title="Replacement O-Ring for 4-Inch Membrane Housing Pressure Vessel SS or PVC" template="product/widget/link/link_inline.phtml" id_path="product/188"}} O-Ring for End Plug - Internal
{{widget type="Magento\Catalog\Block\Product\Widget\Link" anchor_text="3850.005" title="Plug for Membrane Housing Feed-End Permeate Port" template="product/widget/link/link_inline.phtml" id_path="product/232"}} ½"Plug for Permeate Port on Feed End
{{widget type="Magento\Catalog\Block\Product\Widget\Link" anchor_text="H-C111DC" title="O-Ring Lubricant" template="product/widget/link/link_inline.phtml" id_path="product/488"}} Lubricant for O-Rings,
DOW Corning 111, 5 Oz
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: 97980762221

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4.8 ★★★★★
Based on 12 reviews
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Verified Purchase
Finngirl
Fort Morgan, US
★★★★★ 5
Good quality, smooth feel
I got these briefs so recently that have washed just one pair so far. First off, these are very comfortable, the material is soft & bordering silky, good quality sewing. Wash well and minimal if any shrinkage. They do come a bit wrinkled from the dryer but hey, these are underwear and will go on smoothly. If it were a t-shirt, I would look sloppy. I feel the sizing is accurate. No rolling and these don't announce themselves under clothing. Planning on getting more of these boxers and replacing my old panties.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 31, 2026
S
Verified Purchase
Skurtzo
Los Angeles, US
★★★★★ 4
A little snug on the thighs
Size: Medium, Color: Multicoloured G (5-pack)
Super comfy, soft and thin. For reference, I'm 5'6", 135, athletic build. I bought medium. I almost returned them because I thought they were a bit too snug on my thighs, and my thighs are not large at all. I was concerned about panty lines under snug clothing. But, because they're thin, I figured they would probably stretch, so I kept them. So far, I've only worn them under a night shirt, but they're super comfortable and they dont ride up at all. Very nice, but if your thighs are a little thick, you probably won't like them.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on August 29, 2025
S
Verified Purchase
Shanna
Omaha, US
★★★★★ 5
Functional + Sexy
Size: Small, Color: Multicoloured E-(5-pack), Size: Small, Color: Multicoloured E-(5-pack)
Not only do these feel good, my husband can’t keep his hands off me. They fit so good and are soft. I change into these to sleep but also just use them as shorts to wear around the house. They’re comfortable and don’t slide around. I got a size small and I’m 100lbs.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 13, 2026
C
Verified Purchase
ClairY
Charlottesville, US
★★★★★ 5
Finally!
Size: X-Large, Color: All Black D (5-pack)
Finally, comfortable underwear that don’t end up giving me a wedgie. I have a round booty and most cuts of underwear end up shifting as I walk and sit. The hem of the underwear comes right under my cheeks and the lightweight material ensures there’s no panty line and no shifting to where I don’t want them! I’m definitely purchasing more.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 17, 2026
A
Verified Purchase
Amazon Customer
Lexington, US
★★★★★ 3
Ehh
Size: Medium, Color: Multicoloured E-(5-pack)
Very thin, still comfy but very thin material. Super soft though. I've worn and washed and they have held up but I won't be repurchasing bc these are so thin
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 14, 2026

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