According to the different volume of the backpack, the backpack can be divided into three categories: large, medium and small.
The large backpack has a capacity of more than 50 liters and is suitable for medium and long distance travel and more professional adventure activities. For example, when you are going to a region like Tibet for long-distance travel or mountaineering, you should definitely choose a large backpack with a volume of 50 liters or more. Some short- and medium-term trips require a large backpack if you need to camp in the wild, because only it can hold the tents, sleeping bags and sleeping mats you need for camping. Large backpacks can be divided into mountaineering bags and long-distance travel backpacks depending on the purpose.
The mountaineering bag is generally long and thin, so that through the narrow terrain, the bag body is divided into upper and lower layers, and the middle is separated by a zippered interlayer, which is convenient when picking up and placing articles. The sides and top of the backpack can be tied to tents and mats, which invisibly increases the volume of the backpack. There is also a hail cover outside the backpack for bundling hail and poles. The most noteworthy is the back structure of these backpacks. The bag has a lightweight aluminum alloy inner frame that supports the package. The shape of the back is ergonomically designed. The back bandwidth is thick and the shape is in line with the physiological curve of the human body. The "S" design, as well as the chest strap that prevents the strap from sliding to the sides, makes the backpacker feel comfortable. And these backpacks all have a strong, generous and comfortable belt, the height of the strap can be adjusted. The user can easily adjust the strap to the height that suits you, depending on your size. Usually the bottom of the backpack is above the buttocks, which transfers more than half of the weight of the backpack to the waist, which greatly reduces the burden on the shoulders and reduces shoulder damage caused by long-term load.
The body structure of the long-distance travel backpack is similar to that of the mountaineering bag, except that the bag body is wider and has a plurality of side pockets for sorting the odd-numbered objects. The front face of the long-distance travel bag can usually be fully opened, and the articles are very convenient to pick and place.
Medium-sized backpacks are generally between 30 and 50 liters. These backpacks are more versatile, with 2 to 4 days of field trips, travel between cities and some long-distance non-camping self-help trips. Medium-sized backpacks are a good fit. It is. Carry-on clothes and some everyday items can be worn. The style and variety of medium-sized backpacks are more diverse. Some backpacks have some side pockets that are more conducive to dispensing items. The back structure of these backpacks is roughly the same as that of a large backpack.
Small backpacks have a capacity of less than 30 liters. These backpacks are mostly used in cities. Of course, it is also suitable for 1~2 days of outings.