Fox 40 Micro Whistle vs Pieps Micro BT

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

Fox 40 Micro Whistle is the lighter option — 165 g lighter than the Pieps Micro BT (94% less weight). If grams matter to you, that is the one to beat.

Spec	Fox 40 Micro Whistle	Pieps Micro BT
Weight	10 g · 0.010 kg · 0.02 lb	175 g · 0.175 kg · 0.39 lb
Brand	Fox 40	Pieps
Category	Safety	Safety

Fox 40 Micro Whistle

10 g

Pealess safety whistle audible up to 1km.

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Pieps Micro BT

175 g

Digital avalanche transceiver for winter mountain travel.

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Fox 40 Micro Whistle vs Pieps Micro BT: which should you buy?

If saving weight is your priority, the Fox 40 Micro Whistle wins — at 10 g it is 165 g (94%) lighter than the Pieps Micro BT (175 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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