The Sea to Summit Airstream Pump Sack is a large volume pump for Sleeping mats. This 20 litre airstream bag can be inflated with one breath, two or three runs from the airstream is enough to inflate any of the Sea to Summit Sleeping mats. The Sea to Summit Airstream Pump Sack also doubles up as a 20 litre dry sack making it a truly useful addition to your collection of kit. Sea to Summit Airstream Pump Sack Features: Ultrasil Fabric Seam Sealed Oval Base 20 Litre Capacity