Lowepro Whistler BP 350 AW Photo Camera Sling Backpack + Accessory Bundle For Canon, Nikon, Sony, Olympus, Pentax Digital SLR Cameras This pack was designed and tested by professional photographers, including Whistler shooter Paul Morrison, in the extreme conditions of the Coast Mountains of British Columbia, Canada. ActivZoneTM harness system provides targeted padding and support for comfort on the move. Pack includes a detachable All Weather AW CoverTM to deploy as needed and protect valuable gear from rain, snow, dust and sand. Professional photographer Paul Morrison suggested we add a hinged back panel/zipper for partial or full access to gear; so we did. This hinged back is a handy feature for reaching gear in inclement weather. A very roomy front pocket expands to fit alpine essentials. A waterproof barrier separates wet gear from the main compartment (drain holes at bottom).