Featuring a waterproof valve that purges trapped air, SealLine's versatile Blocker PurgeAir Dry Sack resists ballooning to help maximize use of space within a pack or bag. Plus, the fully waterproof construction ensures essential contents are protected.. . Versatile materials: Lightweight 70D polyurethane-coated nylon materials are a tougher, more resilient cousin to the ultralight BlockerLite materials. More durable and versatile, these materials are great for all-around use with confident waterproof protection.. PurgeAir??-equipped: Unique and waterproof PurgeAir valve vents trapped air, helping the sack compress further after being sealed, and are both more durable and more reliably waterproof than waterproof/breathable fabric membranes.. Waterproof closure: Roll-top closure features a wrinkle-free stiffening strip to ensure a secure seal when closing the dry sack.. Durable construction: Fully welded seams result in stronger and more durably protective construction compared to sewn-and-taped seams.. Efficient-Packing: PackTight?? packing system sacks feature flat-sided, rectangular shapes that nestle closely together, packing 20% more efficiently than rounded sacks for easy, space-saving organization.. Weight: 2.9 oz.. Measures 4.7 x 9.2 x 16.1. Volume: 915 cu. in./15L. PVC-Free: Yes. Closure: Roll-down. Material(s): 70D polyurethane-coated nylon. Spot clean. Imported.