Portable Outdoor Hollow Fibre Water Filter Straw

The stream runs clear over the stones and you have no idea what is upstream of it.

You unscrew the outlet cap, kneel at the edge, and push the ported base under the surface until the collar is wet. The first pull is hard because the membrane is dry. The second comes easier. What you taste is cold water and, faintly, nothing at all, because a bed of coconut activated carbon sits between the membrane and your mouth. The lanyard is around your wrist the whole time, which is the small detail that stops a 60 g tube going down the current.

The straw is an ABS tube about 22 cm long and 2.5 cm across, weighed by the maker at 60 g. Its own printed card names what is inside: a hollow fibre membrane and coconut activated carbon, behind a threaded inlet at the bottom and a capped mouthpiece at the top. The card gives a flow of 750 ml a minute and a five year shelf life. Four kits are offered, from the straw on its own up to a set with an extension tube, a carabiner, a backflush syringe and a collapsible water bag.

Key Benefits

• Two stages, both named The maker names a hollow fibre membrane and coconut activated carbon, and prints a cutaway showing where each one sits. Most straws in this price band name neither.
• 60 g on the maker card Light enough that it stays in the pack all season rather than being left behind on the short walks.
• Backflush syringe on kits three and four Pushing clean water back through the membrane is how the flow is restored. That tool is what makes the working life figure mean anything.
• Water bag on kit four A collapsible bag screws to the inlet, so you can fill at the stream and drink at camp rather than lying at the bank twice.
• Nothing to charge or replace No battery, no cartridge to buy, no chemical dose to measure. A cap, a tube and a lanyard.

Best for: hikers, campers and cyclists carrying less water than the day needs, and anyone who wants a light tube in the pack for the stretch between two known taps.

Why It Works

Hollow fibre is a bundle of very fine tubes with porous walls; water is pulled through the wall and whatever is too large to pass stays outside. The carbon bed behind it is there for taste and odour rather than for anything else. Both of those are material facts about how the object is built, and they are the only kind of statement we will make about it. The maker prints a percentage on its sleeve and we do not endorse it. No test report, no standard and no rating in microns comes with this straw, so we make no hygiene or health claim for it, and it should not be treated as a substitute for water you already know is fit to drink.

Quick Product Facts: hollow fibre membrane with coconut activated carbon, as named on the maker card; BPA free ABS body; 60 g net on the maker card; about 22 cm long and 2.5 cm across on the supplier sheet; flow given as 750 ml per minute; working life quoted here as 1000 litres, the lower of the two figures the maker publishes; shelf life given as five years; wrist lanyard; four kit options.

How It Fits Your Routine

Wet it at home first. A dry membrane pulls hard and people conclude the straw is faulty when it is simply new. Two minutes at the kitchen tap tells you what a normal pull feels like, and gives you a baseline for when the flow later drops.

On the hill it lives in a hip pocket, not the bottom of the pack. The point of a 60 g straw is that it is reachable at the stream you did not plan to stop at. On kits three and four the bag rides in the same pocket, folded flat.

Backflush it before it goes away, not after. Fill the syringe with clean water, push it through from the mouthpiece end, and let the straw dry with both caps off. Store it dry, and keep it out of a freezing car boot, because the maker gives a working range that starts just above zero.

FAQ

What is the filtration rating in microns? The maker does not publish one, anywhere, on any panel. We will not put a number on it that the maker has not given.

How many litres will it do? The maker card says 1500 litres and the supplier sheet says 1000. We quote 1000, because when two figures from the same source disagree the smaller one is the honest one to plan around.

What temperature range does it work in? The card that ships with it gives 32 to 90 degrees Fahrenheit, which is 0 to 32 Celsius. The web sheet gives a wider range. Plan around the card, and do not let it freeze with water inside.

What are the printed figures on the sleeve? They are the maker's own wording and we do not adopt them. Sold as a hollow fibre filter straw for outdoor use. No test report and no standard is supplied with it, and we claim no health or hygiene property for it.