The Hyperlite Mountain Gear Crux 40 is a ski mountaineering pack with a 40 L main compartment plus a 15 L extension, for 55 L total, built from Dyneema Woven Composite 5.0 for waterproof strength at low weight. At 1250 g it carries a rated 22.68 kg maximum load, and a zippered back panel gives full access to the main compartment without unpacking through the top - useful for reaching layers or a rope mid-tour without disturbing everything else.
Internal pockets are sized for avalanche tools (probe and shovel), keeping rescue gear separate from the rest of the load and quick to reach. Skis carry either A-frame or diagonally, covering both bootpacking and skinning approaches.
It is built specifically for ski touring and mountaineering, not general backpacking - the ski-carry system, avalanche-tool organisation and load rating point squarely at winter and shoulder-season alpine objectives rather than three-season trekking.