The Airstream is our big-volume sleeping mat pump. It's based on our 20 litre Ultra-Sil Nano dry sack with an added valve plug and foot loop. Using the venturi effect means the Airstream can be inflated with a single breath. Two to three cycles from the Airstream are enough to fill our mats, meaning you're ready to go quickly, with minimal breath condensation in your mat, or dizziness from blowing the mat up. The Airstream can be used as a 20L dry sack, or as a vacuum bag to store your down sleeping bag. Inflates most sleeping mats in only two or three breaths Oval base design Fully seam sealed with sealable valve plug Made from lightweight 15D UltraSil