Set of 4 metal tips that you can add to the aglet of your shoelaces.They slip on the end of the lace and attach with a small screw.
The size of the hole is approximately 4.3 mm.
Myya metal aglets is a great product, not only for shoelaces, but also for many purposes, such as hoodies, boots, sneakers, drawstring, etc. As for how to use it perfectly, please use your unique imagination. For example,
1) If you are worried that it is a bit heavy and may cause the laces to be pulled off and loosened, you should double knot the laces;
2) If you are worried about them hitting together, you can tie a knot higher on one side and lower on the other side, or hold it down with shoelaces;
3) If you overtighten them they will drill into the lace and pass entirely through the screw hole. The frequently-mentioned electrical tape was a big help in keeping this from happening
4) If you want to fix it on the rope permanently, it is recommended to use a drop or two of liquid glue in the aglet before finally securing the screw. A little insurance for keeping the drawstring/ribbon/lace in place.
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In short, different uses have different techniques.