Here's what other sites are saying:
Dry bags aren't just for the river anymore. The Westwater Backpack protects your valuables from splash, spray, or the unexpected rain storm during a portage or overnight camp.The Westwater waterproof backpack is ideal for portaging or hauling gear from the boat to the campsite.Keep your gear dry even when submerged! Easy-to-use ZipDry(R) Seal presses shut like a freezer bag.420 denier Cordura nylon ripstop with a heavy matte polyurethane finish for abrasion resistance and overall strength.All seams are RF welded and guaranteed to be free of leaks.Padded shoulder straps with grip strips are strategically sewn in to prevent slippage.Waist straps help distribute your load for a more comfortable ride.Size: 32" x 24" x 11", 4900 cu. In., 80 liters.To ensure you receive the best continued performance from your ZipDry Seal, Watershed recommends periodic lubrication with a non-petroleum based product such as 303 UV Protectant, Armor-All or Burt's Bees hand salve.
Watershed's Westwater Backpack is its largest waterproof backpack. This pack offers monstrous storage space and a completely watertight construction and top closure. Pack the Westwater to the brim, lash it to the deck of your raft, and submit it to a thrashing in the river. All your gear will stay dry day-after-day, and when it comes time to rock a long portage, the shoulder straps and waist-belt make it that much more comfortable to go the distance.
Watershed Westwater Dry Backpack - TheWestwater Dry Backpack by Watershed is a monster waterproof backpack, offering submersible protection for several days worth of gear. The patented ZipDry seal is similar to a heavy-duty freezer bags zipper. It locks shut, keeping out moisture with an airtight, waterproof seal, even when submerged and under pressure. The top-loading cylinder shape with side compression straps allows you to adjust the height when loaded. The polyurethane-coated 420-denier nylon pack cloth fabric offers 5 times the abrasion resistance of PVC, stays flexible in cold weather, is UV-stable, and more environmentally friendly. Radio-frequency welding bonds the multiple layers of fabric into a single piece of material, eliminating leaks. Padded, removable shoulder straps and the waist strap help to evenly distribute your load and offers you all the comforts of a backpack. Through intensive quality assurance, including prolonged inflation testing, Watershed produces truly waterproof bags that are guaranteed to be free of leaks. Whether you are kayaking, canyoneering or scrambling around in the rainforest, you will love the Westwater Dry Backpack by Watershed.