Features Enter your model number to make sure this fits. AirZone Centro back system AdaptiveFitTM harness Hipbelt pockets Harness pocket Stretch mesh pocket Description Product Description The Lowe Alpine AirZone Pro 45:55 Backpack is a 4 season hiking pack. The size adjustable Airzone back system is the technological heart to this day pack. Maximum ventilation and minimum body contact is achieved by the Airzone mesh suspension back panel that, unlike similar systems, does not intrude on the internal capacity of the pack. All contact areas have a high wicking fabric and two supportive lumbar pads distribute the weight perfectly. The easily adjusted Adaptive fit shoulder harness allows around 100mm of adjustment to suit a wide back length range and allows maximum ventilation. The load bearing split construction adaptive hip belt wraps your body contours moving with you to evenly distributing weight without restriction. The Airzone Pro 45-55 oozes quality, using lightweight yet durable nylon mini ripstop fabric, bound internal seams with larger fabric tolerances for additional strength, and high quality buckles webbing and zips. Main compartment storage is accessed via the dual strap top lid and gives you 45 litres capacity which can increased by another 10 litres by extending the lid pocket. Additional storage is provided by 7 zipped pockets and two side stretch mesh pockets. A great feature is the side access zip which allows quick access to the bags contents without having to go through the top lid. Walking poles and ice axes can be easily stored on the outside of the pack using Tip Grippers or the webbing loop and the elastic bungee system. Hydration compatible with a large internal bladder sleeve, right hand side pipe port and shoulder harness mounted tube trap. A raincover is also included as the pack is not guaranteed waterproof.