Filters bacteria, cysts and microplastics as you drink. 65 grams, no batteries.
How the KARST filter works
As you scroll, the straw rotates and comes apart, then the view dives into the cut face of its 0.1-micron hollow-fiber membrane. Held at the membrane: sand (100 µm), Giardia cysts (5 µm), and E. coli-class bacteria (2 µm) — all far larger than the 0.1-micron pores. Only water passes through. Nothing bigger than 0.1 microns gets through.
What it is
The cheapest insurance your kit will ever carry.
No pumps, no tablets, no waiting — just lower it in and drink. One straw filters 1,500 liters of untrusted water, catching bacteria, parasites and microplastics up to 0.1 microns.
Specification
- of waterborne bacteria filtered by size exclusion
- 99.9999%*
- rated filter lifespan
- 1,500L
- total weight
- 65g
- hollow-fiber membrane pore size
- 0.1µm
- flow rate
- 600ml/min
- batteries, chemicals or moving parts
- 0
*Based on manufacturer membrane test data (0.1-micron hollow-fiber ultrafiltration; filtration by physical size exclusion).
KARST filters do not remove viruses, dissolved chemicals, heavy metals or salt. Intended for outdoor, travel and emergency preparedness use.
One straw. Different ways to be ready.
Single Straw
- →Drink straight from any stream or tap you don't trust
- →Filters waterborne bacteria, cysts & microplastics at 0.1 µm
- →Lasts 1,500 liters
- →No batteries, no chemicals, infinite shelf life
Two-Pack
$19.00 / straw
- →2× KARST Straws
- →3,000 liters of combined capacity
- →One for your pack, one for your car
- →Never caught without a spare
Family Four
$14.75 / straw
- →4× KARST Straws
- →6,000 liters of combined capacity
- →Get one for the whole crew
- →Keep one in every pack, car, kit and home
In the field
Out where the taps run dry.
