Replacement pump bag/stuff sack for Mountain Equipment's Aerostat mats.
Mountain Equipment says:
The fastest way to inflate your insulated sleeping mat.
Mountain Equipment's Aerostat Mat Pump is a different shape to most of the pump bags out there, it is quite long with a small diameter, but it still does the job. Due to Mountain Equipment utilising Exped's patented valve technologies, this pump bag will also work with Exped mats.