Read the stated micron rating, the flow, and the cartridge life · review
Purewell straw water filter review
A straw filter that publishes both of the figures this shelf usually splits — a 0.01 micron rating and a 1500 liter cartridge life — and names all four stages of its element, while saying nothing about flow, weight or the thread it screws onto.
A 0.01 micron rating, a four-stage element named as a hollow-fiber ultrafiltration membrane, PP cotton, coconut-shell activated carbon and an adsorption ball, a cartridge life of 1500 liters, a BPA-free plastic body the maker describes as medical grade, and a carabiner.
The pair of figures, and the one that is missing
0.01 micron and 1500 liters. These are the two numbers that let one filter be lined up against another: the first describes the element, the second describes how long it is stated to last. Plenty of listings on this shelf publish the liters and skip the microns.
No flow rate. Nothing in the title or the bullets gives liters per minute, and nothing describes how hard the straw draws. On a straw that is the specification you notice first in use.
The thread question
The maker states the filter can be fitted into a water bottle, and never says which bottle. A thread size is the one compatibility figure a straw filter can publish, and this listing has none. If you intend to screw it onto the bottle already in your pack, that is a measurement to take yourself before ordering.
How the maker’s claims are written here
The listing carries a 99.99% figure for bacteria and heavy metals. It is reported here as what it is, attributed and nothing more: the maker states 99.99% of bacteria. Nothing on this page says what the filtered water may be used for — that question belongs to the maker’s own instructions and to the local authority wherever you fill.
Before ordering
Measure the neck of the bottle you actually carry, and read the maker’s instructions on backflushing and on storage between trips. Both are what decide whether an element reaches the liters printed on the box.
Availability
The American Amazon store returned nothing, so the buy link opens a local search rather than a page that is not there.
Every figure here is what Keepa held on the day this page was last revised. Offers and prices shift without warning.
What it does well, and where it gives way
Strengths
Publishes a micron rating and a cartridge life together, which most listings on this shelf do not
Names all four stages of the element rather than calling it a filter, so what sits inside the housing is known before ordering
The body material is stated as BPA-free plastic, described by the maker as medical grade
Compromises
No flow rate at all, so how long a liter takes through a clean element is unknown
No weight, on a format bought precisely because it is small
The thread is never dimensioned, so whether it meets a 28 mm (1.10 in) PET neck or a soft flask cannot be established from the listing
Where this model is listed
A listing is not an offer: the reference exists on these stores, availability changes daily.
France
Germany
Spain
Specifications
Micron rating
0.01 micron — stated twice, as 0.01 μm in the title and as a filtration accuracy of 0.01 micrometer in the bullets
Filter element type
Four stages, all named — a hollow-fiber ultrafiltration membrane, PP cotton, coconut-shell activated carbon and an adsorption ball — stated
Stated flow rate
Not published on the listing
Cartridge life
1500 liters — stated
Weight
Not published on the listing
Format
Straw, supplied with a carabiner; the maker states it can be drawn through at the source or fitted into a water bottle
Bottle thread compatibility
Not published on the listing — the maker states the filter is inserted into a water bottle, and never gives a thread size
Amazon reference
B09JGBMMXN
EAN
0725108617225
What people ask before buying
What does a 0.01 micron rating describe?
It is the pore size the maker states for the membrane — how wide the openings in the element are built to be. It describes the element, not the water leaving it, and it is the maker’s own figure rather than anything established here.
What is missing next to the 1500 liters?
A flow rate. Cartridge life says how many liters the element is stated to last for; flow says how long each of those liters takes, and it falls as the element loads. This listing publishes the first and not the second.
Does Purewell publish a stated flow rate?
No. Not published on the listing. What the listing does publish instead is the filter element type: Four stages, all named — a hollow-fiber ultrafiltration membrane, PP cotton, coconut-shell activated carbon and an adsorption ball — stated.
Our score
7.2/ 10
Two published figures where most of this shelf gives one, and an element named stage by stage. Everything to do with handling — flow, weight, thread — is left out.
The buyer this one serves, among camping gear
A pack where a straw is carried as a backup and the cartridge figure matters more than the handling.
Amazon reports what buyers took in the month before this page was last checked: at least 50.
The figure is a floor, rounded by Amazon, and read through Keepa — it says what buyers picked, not what a maker claims.
Sources
Specifications: the manufacturer sheet for camping and hiking gear and the matching Amazon product page. Prices and availability: Keepa. Every figure on this page names its source.
0.01 micron, doubled, stated · six-level system with UF membranes, PP cotton, KDF and carbon · 700 ml/min from an electric pump · 168 liters per charge, which is not a cartridge life · 350 g (12.3 oz) · 1.5 m (5 ft) hose · emergency light
The only electrically pumped filter in this group — six stages, a 1.5 meter (4.9 ft) hose and 700 milliliters a minute — publishing a liters-per-charge figure where this shelf asks for a cartridge life.
Best for: Group use at a vehicle camp, where pumping by hand for twenty liters is the thing you want to avoid
Press filter bottle · 500 ml · 0.2 micron stated · hollow fiber with carbon · 1500 liter cartridge
A 500 ml press bottle that publishes volume, pore size, element type and cartridge life — four of the seven columns this hub compares — and quotes the coarsest micron figure of the six filters here that give one.
Best for: A short walk or a run where one small bottle refilled at the stream is the whole water plan.
Press bottle · 710 ml · 250 liter replaceable cartridge · no pore size published
A 710 ml press bottle with a replaceable cartridge rated at 250 liters, and the most talkative claim list on this shelf — every one of which is written here as the maker’s claim, because no pore size is published to check any of it against.
Best for: Travel where one bottle is treated at a time and the cartridge is expected to be replaced as a routine cost.
