One problem with avalanche airbags—they’re permanently built into the backpack. That means if you want a bigger pack for, say, a hut trip, or a small pack for light-and-fast day tours, you need two very expensive packs. The North Face solved that problem by designing an ABS airbag system that is independent of the backpack and can, as TNF claims, turn any pack into an avy pack. The two side pods contain the avalanche airbag system and nitrogen canister, and the harness system can be affixed to any pack with two shoulder straps.