When you purchase this nylon protector with a prong dog collar in one order, we will choose its size to fit the collar. You will not have to adjust it by yourself.
In case you purchase a nylon cover separately, count the number of links of a collar you already have. A standard size usually counts 10 links. If you have extra, just choose the option corresponding from the dropdown list.
Or it is easy to adjust by yourself. Just measure the length of your metal dog collar, and cut extra length of the nylon protector to fit exactly your prong dog collar size. Scorch along the edges of the nylon prong collar cover with the lighter to make them durable and prevent coming the threads out.
In case you will need a larger nylon cover for a prong collar with extra links, you are welcome to order a new custom-made nylon protector that will fit your pinch collar. Just choose the collar size in the dropdown list at the page top.