The Lightning series of packs (Lightning 45 & Lightning 60) are often thought of as backpacking packs. They certainly are outstanding for this application, no doubt about it. In fact, they were designed with backpacking and thru-hiking as the primary activities. But during the months and years of development (and since) it became clear that these packs would have much broader capabilities.
Much of this is due directly to the frame and harness system, which does an excellent job of 1) transferring load to the hips and 2) stabilizing the load. These attributes lend themselves equally well to snowshoeing, backcountry skiing and mountaineering. The Lightning 60 in particular has the volume to accommodate bulkier winter gear, such as extra layers of clothing, bulkier sleeping bag, winter tent, etc. Skiing and snowboarding with a heavy load is perhaps the ultimate test of a pack's load control capabilities and the Lightning passes that test. It is a cleanly designed pack with no bells and whistles, but don't let that fool you. It's got guts!