The Mountain Vest is a lightweight, versatile, backpack replacement. Although the Mountain Vest does not have the avalanche airbag technology of the Avi Vest, it has many of the same features: water tight pockets in the front allowing the user to carry radio's and phones, storage space in the back to carry a shovel, probe and an extra layer of clothes, as well as a ski carrier system. All in a package that weighs less than 3lbs!