SKU: 25375443465

4" x 40" | 2350 GPD | 100 psi | 99.2% Rej. | Hydranautics ESPA Ultra-Low Pressure Membrane (Replaces ESPA4-4040)

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Description

4" x 40" | 2350 GPD | 100 psi | 99.2% Rej. | Hydranautics ESPA Ultra-Low Pressure Membrane (Replaces ESPA4-4040)Hydranautics ESPA4 LD 4040 4" x 40" Membrane Element Combining energy efficiency with high rejection Hydranautics ESPA4 LD 4040 is the lowest feed pressure membranes offering low energy consumption. ESPA4 LD 4040 membranes require ultra low pressures without compromising high salt rejection and are commonly used in the second pass of a reverse osmosis system. The ESPA4 LD 4040 membrane is designed with Low differential (LD) Technology to minimize


Hydranautics ESPA4-LD-4040 4" x 40" Membrane Element

Combining energy efficiency with high rejection


Hydranautics ESPA4-LD-4040 is the lowest feed pressure membranes offering low energy consumption. ESPA4-LD-4040 membranes require ultra-low pressures without compromising high salt rejection and are commonly used in the second pass of a reverse osmosis system.

The ESPA4-LD-4040 membrane is designed with Low differential (LD) Technology to minimize colloidal fouling when used with conventional pre-treatment equipment. Hydranautics ESPA4-LD membranes offer consistently low feed pressures and longer intervals between cleanings.

ESPA4-LD-4040 is the replacement for Hydranautics ESPA4-4040 membrane element, which has been discontinued by the manufacturer.

The energy required to pressurize RO feed water is the largest contributor to the total energy consumption of the RO plant. ESPA membranes are the choice for applications demanding high-energy efficiency, with uncompromised productivity and salt rejection. Operating at significantly lower pressures, ESPA elements produce high quality water in a range of water treatment applications, ensuring energy cost savings.

ESPA membranes are used in the treatment of drinking water, industrial process waters, municipal and industrial waste water recovery and reuse because of this exception performance capability. These membranes also serve as part of polishing units in seawater desalination plants when boron rejection is critical.

ESPA4-LD-4040 Specifications

Manufacturer Model: ESPA4-LD-4040
Brand: Hydranautics Nitto
Replaces Model: Hydranautics ESPA4-4040
Permeate Flow: 2,350 gpd (8.9m3/day)
Salt Rejection: 99.2% (99.0% Minimum)
Test Feed Pressure: 100 psi (0.7 MPa)
Test Temperature: 77°F (25°C)
Test Recovery: 15%
Test pH Range: 6.5 to 7.0 pH
Test Feed: 500 ppm NaCl Solution
Configuration: Spiral Wound
Membrane Polymer: Composite Polyamide
Membrane Active Area: 80 ft2 (7.4 m2)
Feed Spacer: 34 mil (0.864 mm)


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SKU: 25375443465

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Allison L
Los Angeles, US
★★★★★ 5
My favorite socks now!
Size: Medium, Color: Deep Sea/Breaker Blue/Electro Pink
I love socks! And these are quickly becoming my favorites! They do not slide down into your shoe no matter if you are working out or just wearing them for normal everyday use. The price is a little higher than I would normally pay for 3 pair of socks, but after wearing these for a few weeks, I think the quality and comfortability of these socks is well worth the money.
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Reviewed in the United States on November 1, 2023
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SS
Natrona Heights, US
★★★★★ 5
Happy!
Size: Medium, Color: Deep Sea/Breaker Blue/Electro Pink
Happy with the comfort and quality of these socks. I would buy again!
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Reviewed in the United States on September 29, 2025
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E W.
Lowell, US
★★★★★ 4
Great fit and cushioning
Size: Medium, Color: Deep Sea/Breaker Blue/Electro Pink
Great fit for running and nice cushioning for tennis
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Reviewed in the United States on April 11, 2024
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Tracy Canfield
Bozeman, US
★★★★★ 5
Quality, comfort and support.
Size: Medium, Color: Deep Sea/Breaker Blue/Electro Pink
These socks are the bomb! If you are athletic or on your feet for extended periods these great looking, well made socks are constructed to offer just the right amount of compression and support. The toe is soft and thick. I will order these again and again. Hopefully Amazon will add even more color choices on the future.
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Reviewed in the United States on December 3, 2022
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Heather H Ansley
Phoenix, US
★★★★★ 5
Goldilocks of socks!
Size: Medium, Color: Deep Sea/Breaker Blue/Electro Pink
Great socks....good support - the goldilocks. Not too thick or too thin; stay up nicely. Love the colors!
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Reviewed in the United States on January 30, 2024

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