Many schoolbags are closed by zipper, once the zipper is damaged, the whole bag is basically scrapped. Therefore, the bag custom zipper selection is also one of the key details.
Zipper is composed of chain teeth, pull head, up and down stops (front and back) or locking parts, among which chain teeth are the key part, which directly determines the side pull strength of the zipper.
To identify the quality of zippers, first observe whether the chain teeth are aligned neatly, whether there are broken teeth, missing teeth, etc., and then touch the surface of the chain teeth with your hands to feel whether it is smooth. It is normal to feel smooth without rough burrs. Then pull the pull head repeatedly to feel whether the connection between the pull head and the zipper is smooth. After tightening the zipper, a part of the zipper can be bent with slightly greater strength, and the zipper teeth can be seen to have cracks when bending. After looking at the cohesion gap between the pull card and pull head, if the gap is large, pull card and pull head between easy to break, inconvenient for subsequent use.
The poor quality of zipper greatly affects the use of the bag experience, it is easy to have problems, such as tooth, mask, empty, exploding chain and other problems, so, to the bag quality is good, the zipper quality is also good.