Membrane Solutions S2 Water Filter Straw 4 Pack
- Item Weight: 0.19 pounds
- Purification Method: Activated Carbon, Hollow Fiber Membrane
- Maximum Flow Rate: 500 milliliters per minute
- Container Type: Bottle,Syringe,Tube
Last refreshed Sep 7, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
Stocking multiple kits is where this pays off, with NSF testing behind the filtration claims and a cold-weather limitation worth planning around.
As an Amazon Associate I earn from qualifying purchases. ProductDome earns a commission when you buy through links on this page.
ASIN: B08MQMC8PLModel: S2Category: Camping Water Filters
Styles Available
Need a different one? Pick on Amazon →
Overview
The Membrane Solutions S2 is a 4-pack of detachable water filter straws rated to NSF/ANSI 42, 372 and 401, built so the filter cartridge can be swapped without replacing the whole straw. It targets campers and preppers who want backup filtration on hand.
The detachable design is the real differentiator here: most straw filters are sealed units you throw away whole, while this one lets the filter element be replaced separately from the tube.
- 0.1 micron four-stage filter cartridge
- Detachable mouthpiece for bottle backwashing
- Flow rate up to 500 ml per minute
- Pack of four for spares or sharing
Who it's for
Suited to anyone assembling redundancy into an emergency kit, since 4 units cost less per straw than most single-pack filters. Less useful for someone who wants one heavy-duty filter for constant trail use rather than several backups.
Pros and cons
- NSF/ANSI 42, 372, 401 certified filtration
- Detachable cartridge replaces without a new straw
- Works directly with standard water bottles
- Four units add backup redundancy
- Freezes and stops working in cold weather
Performance notes
Filtration runs through a 0.1 micron hollow fiber ultrafiltration membrane, a coconut shell granular activated carbon stage, and a double PP fiber filter, tested to NSF/ANSI 42, 372 and 401 standards. Flow is rated up to 500 ml per minute, and the detachable mouthpiece connects to a standard bottle for backwashing instead of requiring a separate syringe.
Specifications
| Brand | Membrane Solutions |
|---|---|
| Model | S2 |
| Dimensions & fit | |
| Item Weight | 0.19 pounds |
| Item Dimensions L x W x H | 8.7 × 1.6 × 1.6 inches |
| Capacity & performance | |
| Maximum Flow Rate | 500 milliliters per minute |
| Capacity | 1320 gallons |
| Power & efficiency | |
| Power Source | Corded Electric |
| Construction & materials | |
| Material Type | Straw |
| Compatibility & installation | |
| Installation Type | Personal Container |
| Included components | |
| Unit Count | 4 |
| Included Components | Filter |
| Warranty & support | |
| Supported Water TDS Level Maximum PPM | 1000 |
| Other details | |
| Purification Method | Activated Carbon, Hollow Fiber Membrane |
| Container Type | Bottle,Syringe,Tube |
| Number of Items | 4 |
| Part Number | Versatile Water Filter Straw |
| Other Special Features of the Product | Portable |
Frequently asked questions
What makes the Membrane Solutions S2 straw 'detachable'?
Both ends of the straw come apart, so when the filter element wears out you replace just that cartridge instead of buying a whole new straw, which the description positions as the main cost saving over sealed one-piece filter straws.
Is the S2 filter straw certified, or just marketed as one?
It is listed as tested to NSF/ANSI 42, 372 and 401 standards, covering reduction of odor and particulates while confirming lead-free materials.
Does the Membrane Solutions S2 work in cold weather?
One reviewer's own camping trip is the clearest data point here: the filter froze and stopped working in freezing temperatures, so it should be kept from freezing or thawed before use in cold conditions.