UltraFlask+ 500ml + Filter Kit

Lighten your load and drink right from the source. We took our go-to flask and added filtration to create a system that delivers hydration without contamination. The filter — light and compact — screws on top so you can drink right from the flask. Or — if you’re carrying more water — use the system to fill a bottle or reservoir.

FAST & SAFE FILTRATION
The integrated filter removes Escherichia coli bacteria, Cryptosporidium parvum cysts, and Giardia Lamblia from approximately 1,500 liters of water at a rate of >1L per minute.*

SECURE GRIP
A flexible and structured grip makes it easy to hold the flask while screwing and unscrewing the filter.

VEST PACK FIT
Soft material conforms to most hydration packs and larger vest pockets for a secure and stable fit.

HIGH-FLOW
Easy to drink bite valve auto-seals after each sip, eliminating annoying drips.

LARGE OPENING
42mm opening lets you fill the flask easily at any water source.

COMPRESSIBLE
Flexible design shrinks as you drink, minimizing water movement.

INCLUDED BACKFLUSH ADAPTER
Plugs into filter valve and threads onto a HydraPak Stow or bottle of clean water for backflushing the filter to restore its flow rate.

Replacement Parts:

• Filter caps
• Bite valves

*Effectively removes common waterborne bacteria, such as E.coli (99.999%) and parasitic cysts (99.9999%) per HSF 42.