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Acme Tornado 636 vs ACR Electronics Bivy Stick

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

Acme Tornado 636 is the lighter option — 88 g lighter than the ACR Electronics Bivy Stick (88% less weight). If grams matter to you, that is the one to beat.
Spec Acme Tornado 636 ACR Electronics Bivy Stick
Weight 12 g · 0.012 kg · 0.03 lb 100 g · 0.100 kg · 0.22 lb
Brand Acme ACR Electronics
Category Safety Safety
Acme Tornado 636
12 g

Loud pealess emergency whistle. Standard SAR equipment.

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ACR Electronics Bivy Stick
100 g

Compact two-way satellite communicator with SOS, GPS tracking and app-based messaging over the global Iridium network.

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Acme Tornado 636 vs ACR Electronics Bivy Stick: which should you buy?

If saving weight is your priority, the Acme Tornado 636 wins — at 12 g it is 88 g (88%) lighter than the ACR Electronics Bivy Stick (100 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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