The zipper is a connecting piece that relies on continuously arranged chain elements to make the items merge or separate. The more famous zippers have YKK and YBS, and the high-end backpacks generally use YKK zippers. The relationship between the good and the bad of a backpack and the zipper is very large. If the quality of the zipper is not good, then the backpack will be very troublesome to use.
The webbing is generally divided into Nylon and Poly. Nylon's webbing is of good quality and soft to the touch, but the cost is relatively high. It is usually only used by high-end backpacks, while Poly's webbing is more common, and most of the backpacks use Poly webbing.
3, the buckle
Backpack buckles are generally divided into buckles (also known as side-opening buckles), day buckles, ladder buckles, hooks, and rope buckles, as well as some special-purpose fasteners.
On the backpack, the role of the foam is very important, and the common ones are PU cotton and PE cotton. PU cotton is a sponge we often say, that is, there are many holes, it is very soft, and it is generally used in close to the user's body. PE cotton is a kind of plastic foaming material with many small bubbles in the middle, which can maintain a certain shape and is generally used to support the shape of the backpack.