Osprey AirCover Travel Pack Cover Colour:Black The Ultra D is similar

The Ultra D is similar in size to the Ultra O but with even greater strength due to the back configuration

Lock mode also prevents accidental use when stored in either a pack or a pocket

an insulated comfort Gore-Tex® membrane and a removable and adjustable tongue

and for passing intermediate anchors

Osprey AirCover Travel Pack Cover Colour:Black The Ultra D is similarFor those planning to travel with their hiking, backpacking or trekking pack, the AirCover does double duty as a durable cover with a zip back closure to fully encase and protect your pack on the bus, train or plane, as well as a raincover when you hit the trail. Comes in two sizes to fit most packs.