Buy Now, Pay Later
As low as
$9
/ mo
Learn more
- – 4-month term
- – No impact on credit to apply
- – Instant approval decision
- – Secure and straightforward checkout
Ready to go? Add this product to your cart and select a plan during checkout.
Payment plans are offered through our trusted finance partners Klarna, Affirm, Afterpay, Zip, Apple Pay, and Google Pay. No-credit-needed leasing options through Acima may also be available at checkout.
Learn more about financing & leasing here.
Selected Option
Free shipping on this product
30-day returns
Learn more
FREE 30-day refund/replacement
To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
Availability:
15 left in stock
Arrives
Oct 2 – Nov 3
Recently Viewed
Style: 6L-Blue
Features
- Built for Group Camping - Designed for camping, backpacking, and emergency preparedness, this 6L gravity water filter system provides fresh drinking water for 36 people. Ideal for basecamp, group trips, and survival situations where water matters most.
- NSF Tested & Certified - Independently tested by NSF & SGS and meets NSF/ANSI 42, 372, and 401 standards. This portable water filter helps reduce chlorine, sediment, and odor from lakes, rivers, and streams.
- Advanced 4-Stage Filtration - Features a 0.1-micron hollow fiber membrane, coconut shell activated carbon, and dual PP pre-filters. Long-lasting filter delivers up to 1,320 gallons (5,000L) of filtered water while maintaining strong flow performance.
- Gravity-Fed & Pump-Free - No squeezing, no pumping, no electricity required. This gravity water filtration system provides up to 0.5L per minuteperfect for camping, hiking, off-grid living, and emergency water supply.
- Lightweight, Durable & Emergency-Ready - Made with puncture-resistant, BPA-free materials and reinforced hanging strap for rugged outdoor use. Collapsible design packs easily into your backpack while remaining ready for disaster preparedness kits and bug-out bags.
Description
Gravity Water Filter Pro S2 Water Filter Straw C3 Filtered Water Bottle C3 Filtered Water Bottle S2 Replacement Filter Upgrade Filter Straw U3P Gravity Water System
Brand: Membrane Solutions
Special Feature: Chlorine Reduction
Product Dimensions: 3.9"L x 2.3"W x 10.6"H
Material: TPU
Capacity: 6 liters
Included Components: 6L Gravity-fed Water Bag with Adjustable Tree Strap
Package Information: Box
Installation Type: Not Required
Purification Method: Hollow Fiber Membrane
Power Source: Gravity
Other Special Features of the Product: Chlorine Reduction
Container Type: Box
Installation Type: Not Required
Purification Method: Hollow Fiber Membrane
Power Source: Gravity
Maximum Flow Rate: 500 milliliters_per_minute
Supported Water TDS Level Maximum (PPM): 500
Item Dimensions L x W x H: 3.9"L x 2.3"W x 10.6"H
Capacity: 6 liters
Item Weight: 12.8 ounces
Material Type: TPU
Brand Name: Membrane Solutions
Included Components: 6L Gravity-fed Water Bag with Adjustable Tree Strap
Model Name: 6L Gravity Water Filter Pro
Model Number: OESF021_M1
Warranty Description: 1 year manufacturer
UPC: 850071881653
Global Trade Identification Number: 53
Manufacturer: Membrane Solutions
Item Highlight: NSF/ANSI 42, 372 & 401 certified; 0.1-micron 4-stage filter, 1,320-gal life for family camping and emergency water backup
Number of Items: 1
Part Number: OESF021_M1
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Oct 2 – Nov 3
Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
- Klarna Financing
- Affirm Pay in 4
- Affirm Financing
- Afterpay Financing
- Zip Pay in 4
- Financing through Apple Pay
- Financing through Google Pay
Learn more about financing & leasing here.
Similar Products
Top Amazon Reviews
Style: 6L-Blue
While I've not actually been able to test the flow rate of this filter in a gravity configuration, it works exceptionally well with smart water bottles. It filters the water well to make it more clear, it tastes good, and I've not gotten sick even though I've had some very mild immune responses; like one may experience after some vaccinations. From what I understand, this is just my body responding to trace amounts of bacteria which may still get into my clean water from cross contaminating it with dirty hands, and results in resistances to local bacteria. Not unlike how seasonal allergies may be less likely to significantly affect local populations who grew up with those allergens. The instructions are clear and easy to follow, but this whole setup is so intuitive I didn't need them anyway. I like how compact this kit is, rolling up nicely in it's bag, and the wide mouth of the flexible collection bag is very useful for scooping water out of places where a bottle cannot reach it. The system does not seem to leak, and I feel safe drinking the water it filters from running sources. But I still prefer to purify the filtered water I collect from standing sources with some Aquatabs, just in case of pet waste on the trails, or dirty shoes walking through the mud.
...
show more
Reviewed in the United States on September 26, 2025 by Raven Kenneth
Style: 6L-Blue
I bought this as a gift for my son that loves hiking and camping. He has enjoyed this product very much. He has carried it on many hikes and camping trips. Uses it for fresh drinking water and if cooking something over a campfire. I would recommend this product and I would purchase again.
Reviewed in the United States on March 9, 2026 by Sheila C.
Style: 6L-Blue
UPDATE: I emailed the company about filter not working and they got right back to me. They asked a couple of questions and have mailed me a replacement filter. They were very responsive and easy to work with. My new filter is on its way. I will continue to update. I bought this last week. I tested it and worked great! I decided to use again this week just to be sure I have it all down and it has refused to work. The water would go through the hose so I removed the filter and it was not the bag or the hose. The filter itself is not allowing more than a drip through. I tried using it as a straw that did not work. I've taken it apart and can't see any obstructions. I have emailed the company and will update this review once it has been resolved. When it worked, it worked great! And the water tastes clean.
...
show more
Reviewed in the United States on September 21, 2023 by C. VanTassel
Style: 6L-Blue
It clogged really fast, but that could have been user error. It's gravity fed, so it's naturally slow. Other than that, it worked like a charm. Packed up easy, easy to set up, easy to use. Kept us hydrated backpacking through the Uinta mountains. Some other guys had ones that fed into another back so more water was available faster. You might want to look into those types
...
show more
Reviewed in the United States on July 9, 2025 by kORY
Style: 6L-Blue
I recently had the pleasure of using the Membrane Solutions Gravity Water Filter Pro 6L, and I must say it has exceeded my expectations in terms of performance, convenience, and reliability. This innovative water filtration system has quickly become an essential part of my daily routine, and I am thoroughly impressed with its functionality. The primary feature that sets the Membrane Solutions Gravity Water Filter Pro 6L apart is its exceptional filtration capabilities. With a filtration accuracy of 0.1 microns, it effectively removes bacteria, protozoa, sediments, and other contaminants from water sources, providing clean and safe drinking water. The advanced filtration technology ensures that the water you consume is free from harmful substances, making it ideal for outdoor adventures, emergency preparedness, or everyday use. The gravity-fed design of this water filter is a game-changer. It eliminates the need for electricity or complicated installation processes, making it incredibly convenient and easy to use. Simply fill the upper chamber with water, and let gravity do the rest. The filtered water collects in the lower chamber, ready for consumption. This hands-free operation allows you to multitask and ensures a continuous supply of filtered water without any hassle. The capacity of the Membrane Solutions Gravity Water Filter Pro 6L is another impressive aspect. With a generous 6-liter capacity, it can cater to the hydration needs of individuals, small groups, or even families. The large storage capacity is especially beneficial during outdoor activities, camping trips, or in situations where access to clean water may be limited. I appreciate the durable and high-quality construction of this water filter. The BPA-free materials and food-grade components ensure that the filtered water remains safe and free from any potential contaminants. The system is designed to be long-lasting, providing reliable filtration over an extended period. Maintenance is a breeze with the Membrane Solutions Gravity Water Filter Pro 6L. The filter elements are replaceable and have an impressive lifespan, depending on usage and water quality. The filter replacement process is straightforward, and the manufacturer provides clear instructions for optimal performance. In terms of value for money, this water filter is an excellent investment. The combination of its exceptional filtration capabilities, convenience, and durability make it a worthwhile purchase. You can have peace of mind knowing that you are investing in a reliable and efficient water filtration system that provides clean and safe drinking water. In conclusion, I highly recommend the Membrane Solutions Gravity Water Filter Pro 6L to anyone in need of a reliable and convenient water filtration solution. Whether you're an outdoor enthusiast, a frequent traveler, or someone concerned about the quality of your drinking water, this filter delivers on all fronts. With its impressive filtration accuracy, ease of use, and large capacity, it ensures that you have access to clean and safe drinking water wherever you go. Choose the Membrane Solutions Gravity Water Filter Pro 6L and enjoy the convenience of pure water at your fingertips.
...
show more
Reviewed in the United States on September 18, 2023 by Michel Hadorn
Style: 6L-Blue
I researched these life saving water filter straws for awhile before I decided to get this one. The reason I chose this one over the others was because there is known flaw in the filter straws. They work great the first few times and the the water flows through really good and then it goes down to a trickle drip to not working at all. This one particular one, has where you can suck through the straw and fix it, it gets rid of the air bubble trapped inside. The other ones don't have this feature. Also I watched some videos users uploaded when they used the blue bag and got the most swampy water you could get and they filtered it and the water come out clean. It really looks to be the best unit to purchase to have on hand incase tshtf. I have not used my unit, but it arrived clean and looks new and I feel better that I have at least something to get water if the power grid goes down.
...
show more
Reviewed in the United States on February 24, 2023 by F. Bamboo
Style: 6L-Blue
I've been going to the BWCA for 40+ years and have used various filters, capsules and other means to filter water and this is by far the most convenient and easiest filter I've ever used. Packs small and is fairly lightweight, has good water flowage and is easy and quick to fill. Great product!
Reviewed in the United States on July 22, 2025 by Mike