Liberty Mountain Side Release 5/8 inch Buckle with Slider is contoured so it fits the natural bend of your wrist and has two slots to shorten or lengthen the bracelet. This Liberty Mountain buckle has two slots to shorten or lengthen the bracelet, collar, or other project its attached to. The 5/8 inch measurement refers to the opening where webbing or paracord is inserted. Each of the two openings is 5/8". This allows you to make your collar, bracelet, project 1/4 inch longer or shorter.