Lowe Alpine AirZone Trek 45:55 Backpack This AirZone Trek 45:55 is the perfect mid-sized pack for long distance hiking or minimalist multi-day trips, thanks to its redesigned "Formknit" backsystem, versatile pocket layout and a host of buckles and attachments for your various mountain and trail accessories. The AirZone Trek 45:55 has been designed for ultimate comfort and convenience. Crafted from super tough, yet lightweight 210D ripstop nylon with a HydroShield (PU) water resistant coating to ensure long-lasting, durable protection that can stand up to challenging weather. It has also been treated with a durable water repellent for added water resistance, and a rain cover for when its really hammering down. One of the main features of this backpack is the fully redesigned Formknit Airzone + backsystem. This new fully suspended, system creates a gap between your bag and the pack itself, allowing constant airflow during use so you can stay cool, comfortable and forcussed on e