Multi-day walk waterproof bicycle rear pannier bag: multi-day walk through the activities need to carry more equipment, items and food, such as carrying tents and sleeping bags, jackets (winter to bring more cold clothing), changing clothes and socks, toiletries, First aid kits, stove sets of pots, Dodon dinner food and enough energy food, kettle water pockets, headlights flashlight and technical equipment (simple climbing equipment and spare rope) and so on. Due to walking a few days or ten days ranging from their own preferences will carry some personal items, which requires about 45 liters ~ 70 liters capacity of the backpack.