A pack for core users, reflecting feedback from alpine guides. The main compartment is waterproof, allowing you to move freely in rain or snow. It's also durable, with crampon pockets and axe sleeves, designed for alpine use. The rain cover, back frame sheet, and waist belt are detachable. You can customize the weight and specifications to suit your mountain activities. The 50-liter capacity is a basic size for alpine trekking with a tent. It has ski carries on the sides, making it suitable for backcountry use. Recommended activities: alpine climbing, backcountry skiing, and multi-day trekking with a tent. There is some wear and tear. There is no stickiness due to hydrolysis inside. I think it's a functionally excellent bag. For those who want a strong bag that can be used roughly, this is for you.