Arva X Vario 28
Here's what other sites are saying:
Just like skis or snowboards, it can be expensive to own a quiver of backpacks. Arva set out to solve this problem with the X-Over Vario Zip-On ABS Backpack. Either of the bags can be zipped onto an ABS airbag base unit (sold separately), so you get the advantage of having a backpack set that's fully compatible with industry-leading avalanche safety technology. The Arva Zip-On bag carries skis or a snowboard, avalanche safety gear, and a hydration bladder, while the smaller, ultralight pocket gives you bare-minimum storage when you're lapping the lift or tram inbounds. With the X-Over all you need is an ABS base unit, and you've got enough backpack combinations to take you from serious avalanche terrain to light-and-fast shredding at the resort.