The closure mechanism on this hiking backpack is a zipper. One of the materials used to make this bag is polyester and it has a practical inner pocket for smaller items.
From Muziker
Deuter Futura 29 EL Graphite/Shale Outdoor Backpack
The product is available from £99.08 at international stores.
Hardloop
deuter Futura 29 EL - Walking backpack - Men's Graphite / Shale 29 L