Acme Tornado 636 vs Katadyn BeFree 1.0L

Weight and specs compared for 2026 — and which one to choose.

Acme Tornado 636 is the lighter option — 45 g lighter than the Katadyn BeFree 1.0L (79% less weight). If grams matter to you, that is the one to beat.

Spec	Acme Tornado 636	Katadyn BeFree 1.0L
Weight	12 g · 0.012 kg · 0.03 lb	57 g · 0.057 kg · 0.13 lb
Brand	Acme	Katadyn
Category	Safety	Safety

Acme Tornado 636

12 g

Loud pealess emergency whistle. Standard SAR equipment.

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Katadyn BeFree 1.0L

57 g

Flow-optimized 0.1-micron EZ-Clean hollow fiber filter integrated with 1L soft flask. Delivers 2L per minute filtration without pumping.

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Acme Tornado 636 vs Katadyn BeFree 1.0L: which should you buy?

If saving weight is your priority, the Acme Tornado 636 wins — at 12 g it is 45 g (79%) lighter than the Katadyn BeFree 1.0L (57 g). That said, the heavier option may justify the extra grams with more capacity, durability or comfort, so weigh the trade-off against how you'll use it.

See where both rank against everything else in this category on the lightest safety page, or browse the full gear weight database.

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