A: Because the bag has been used for a long time, or got caught in the rain in the process of use, it will lead to the oxidation phenomenon of the metal zipper, which will lead to the rust of the bag and the zipper will not move.
A: Because the bag has been used for a long time, or got caught in the rain in the process of use, it will lead to the oxidation phenomenon of the metal zipper, which will lead to the rust of the bag and the zipper will not move.