Zipper

A zipper, comprising:

• a chain tooth mounting part, the chain tooth mounting part comprising a first mounting belt and a second mounting belt;
• a plurality of first chain tooth parts, mounted on the first mounting belt, each of the plurality of first chain tooth parts comprising a first meshing part and a second meshing part, the first meshing part being located on an outer side of the second meshing part, and a first water-retaining convex flange being provided on two sides of a meshing end of the first meshing part;
• and
• a plurality of second chain tooth parts the mounted on the second mounting belt each of the plurality of second chain tooth parts comprising a third meshing part and a fourth meshing part, the fourth meshing part being located on an outer side of the third meshing part and a second water-retaining convex flange being provided on two sides of a meshing end of the third meshing part;
• wherein the plurality of first chain tooth parts and the plurality of second chain tooth parts have a meshing position and an avoidance position, and when the plurality of first chain tooth parts and the plurality of second chain tooth parts are in the meshing position, the plurality of first chain tooth parts and the plurality of second chain tooth parts are meshed in a staggered manner, and the first water-retaining convex flange and the second water-retaining convex flange corresponding to the first water-retaining convex flange abut against each other in a thickness direction of the zipper.