Katadyn BeFree AC 0.5L Slate Blue Water Filter | Activated Carbon

Katadyn · BeFree AC · 0.5 litres · slate blue

Katadyn BeFree AC 0.5L
filter and drink in one motion

Stop at the stream, fill, run on – no pump, no waiting. 72 grams in your running vest, and the activated carbon core takes the aftertaste out of the water.

Buy the Katadyn BeFree AC 0.5L – the smallest filter flask in the range

The Katadyn BeFree AC 0.5L is a drinking flask with an integrated water filter for trail running, fastpacking and day trips. You fill the soft flask at the stream, screw on the cap and drink straight from it – filtration happens as you drink. What is new in the AC generation is the second stage: behind the EZ-Clean Membrane with its 0.1 µm pore size sits an activated carbon core that reduces chlorine, taste and odour compounds. At 72 grams and 0.5 litres it is the most compact model in the BeFree family and fits the front pocket of a running vest.

0.5 litres – when the small size is the right one

Half a litre sounds like little, but it is exactly the amount you actually need between two water sources while running or on a day trip. In a running vest two flasks sit at the front and stay in view without sloshing. And because refilling at any stream takes seconds, a large reserve is not needed – the water source replaces the volume. If you face longer stretches without water or cook at camp in the evening, the 1.0-litre version serves you better.

Shaking instead of backflushing – and what that means in winter

The EZ-Clean Membrane is cleaned by holding the filter in clean water and shaking it. That is not only more convenient than a backflush syringe, it has a solid advantage in the cold: there is no extra part that can freeze, get lost or stay at home. Frost protection for the filter itself still matters – freezing residual water damages the hollow fibres, and you cannot tell by looking. On winter trips the flask therefore belongs in your sleeping bag or dry in your pack.

What the filter does – and what it does not

The 0.1 µm membrane retains bacteria, protozoa and sediment; the activated carbon reduces chlorine along with taste and odour compounds. Viruses are smaller than 0.1 µm and pass through – in regions with that risk you need additional chemical disinfection or UV treatment. Do not rely on it for heavy metals and salt either: the carbon content of a 0.5-litre flask is too small for that.

Key features – Katadyn BeFree AC 0.5L Slate Blue

• 🥤 0.5 litres Hydrapak soft flask · colour slate blue
• ⚖️ 72 g when empty
• 🔀 Two-stage filtration – EZ-Clean Membrane plus activated carbon
• 🔬 Pore size 0.1 µm · hollow fibre
• 💧 Membrane up to 1'000 L · carbon up to 200 L
• 🔓 Carbon stage unscrews – can also be run without it
• ⏱️ Up to 2 L/min (membrane, without the carbon stage)
• 🦠 Removes bacteria, protozoa, sediment, microplastics
• ⚫ Reduces chlorine, taste and odour compounds
• 🧼 Cleaned by shaking – no tools required
• ♻️ TPU · PVC- and BPA-free · 42 mm thread
• 🚫 Not effective against viruses, heavy metals and salt
• 🇨🇭 Katadyn · Swiss water treatment since 1928

0.5 or 1.0 litres – and when the Gravity version makes more sense

The 0.5-litre flask is built for movement: trail running, fastpacking, day trips in water-rich terrain. It fits the front pocket of a running vest and refills at any stream in seconds. The 1.0-litre version in its double-layer flask is the more robust choice for longer stages and harsher conditions. And if you want to fill several bottles at once in camp or prepare cooking water, a BeFree Gravity serves you better – there gravity does the filtering while you do something else. Buy the Katadyn BeFree AC 0.5L at Swiss-Sale.ch – your Swiss specialist shop for outdoor gear with fast shipping.

Who is the Katadyn BeFree AC 0.5L for?

The 0.5-litre filter flask is for anyone moving light and fast with water available along the way: trail runners, fastpackers, day hikers, bikepackers and travellers who dislike the chlorine taste of tap water.