The lightweight Arcteryx Acrux 40 pack brings forth a new level of performance with its completely waterproof design Similar in construction to the Arcteryx Naos, the Acrux 40 pack has a pared-down, simplistic design. Made with revolutionary 420ACT VaporTight material to keep contents dry. Underneath the removable top lid, the main compartment features a DryBag lid-closure system for easy packing and added weatherproofing. WaterTight zippers on all pockets prevent water penetration. All seams are sealed for weather-tight protection. Hydration-compatible design features reservoir pocket with a waterproof hydroport for drinking tube reservoir sold separately. Radially formed shoulder straps and hipbelt conform to you while you hike, climb and scramble. Webbing hipbelt features removable padded pods that wont interfere with a climbing harness. Front shockcord with cordlock stows a jacket or clothing layer, keeping it within easy reach. All molded components and suspension system are laminated and bonded for superior strength. Monoframe back panel is thin and light with EVA foam, Kydex plastic and 2 aluminum stays to create a direct link between back, suspension and bag. Closeout.