This tough Bergen liner is an ideal supplement for non-waterproof duffels, backpacks or trekking packs. It is especially useful as a side pocket liner & will keep your gear dry & clean. The square shaped base made from abrasion resistant PS33 uses every inch in your pack. This brilliant liner features a broad base loop for holding & easy unpacking. Attention: Closure must be rolled at least 6 times to make it watertight; not submersible!