Hello, this product rope has five thickness specifications, the rope thickness is 1MM (button thickness 2MM),1.5MM (button thickness 2.5MM),2MM (button thickness 3MM),2.5MM (button thickness 3.5MM),3MM (button thickness 4MM), because the button is always 1MM thicker than the rope, so pay attention when choosing the rope, for example, if you choose a 2MM specification, the pendant hole must be larger than 3MM before you can wear it in. You must pay attention to this.