Flex Gravity Bag Water Filter - 3.7L

Brand Lifestraw

The Lifestraw Flex Gravity Bag kit from Lifestraw allows to consume drinking water wherever you are and whatever the origin of the water (river, fountain, stream, etc. with the exception of seawater).

The kit includes a reservoir for water and a filter, in the form of a filter straw. These 2 elements can be used together or separately:

  1. The Gravity Bag tank is flexible and foldable with a large capacity to store large quantities of water (3.7 liters). collapsible tank makes it very compact. It is therefore very easy to transport, fits in a pocket of a backpack and can also be stored very easily in the van, camper van or motorhome.

  2. The Lifestraw Flex straw is the filter ensuring 100% drinkable water. It allows the reduction of lead, chemicals and eliminates bacteria and parasites. This straw is installed on the Gravity Bag tank but can also be installed on a water bottle, a water bag or a bottle.

Very efficient, the Lifestraw Flex straw has 2 levels of filtration to guarantee water without bacteria, without protozoa and also without unpleasant tastes or odors:

  • The first filter is a hollow fiber membrane with 0.2 micron filtration: thus, bacteria, parasites and microorganisms are kept away. It can filter 2000 liters of water. It filters 99.9999% of bacteria (E.Coli, cholera, salmonella…) and 99.99% of protozoan parasites (giardia, cryptosporidie…) that can contaminate water.

  • The second level of filtration is an activated carbon filter. It neutralizes odor and taste so there is no unpleasant taste.

Very versatile, compact and extremely performant, the Lifestraw Flex Gravity Bag Kit helps ensure you have a water source drinkable at your bivouac site, during your hikes, your nomadic trips and road trips in vans, fitted vans and camper vans.


The Lifestraw Flex Gravity Kit is ideal for nomadic travel and to have enough drinking water wherever you are.

  • Gravity Bag dimensions: (L)47cm * (W)25cm
  • Filter straw dimensions: (d)2.5cm *(l) 22.9cm
  • Pipe dimensions: (l) 70cm
  • Weight: 196g
  • Capacity: 3.7 L
  • Filtration: 0.2 micron
  • Autonomy: 2000 liters (water filter)
  • Technology: hollow fiber filter + carbon filter
  • Flow: 0.5 L/min
  • Guaranteed BPA-free

The + for the planet

Lifestraw is a sustainable and committed brand:

  • For every item purchased, a child in need receives drinking water for a year.
  • The company is "Climate Neutral" certified.
  • LifeStraw is a member of many associations and organizations: Conservation Alliance, Outdoor Industry Plastic Impact Alliance, Outdoor Industry Association’s Climate Action Corps, PrAna Responsible Packaging movement.