Pettom Dog Prong Training Chain Collar Stainless Steel Adjustable Pinch Pet Choke Collar with Comfort Rubber Tips Size: X-small Diameter 2.5mm and length 17.7 inch, Small Diameter 3.0 mm and length 19.7 inch, Medium Diameter 3.5 mm and length 21.7 inch, Large Diameter 4.0 mm and length 23.6 inch. Adjustable: Prong training collar suit for all kinds of Small, Medium and Large dog, You can add or remove individual links from the collar as needed to fit your dog's neck. Application: Pull the training dog collar and the dog will stop immediately, The prong collar is great for training aggressive dogs, which are difficult to cope with. Additional blunt cut rubber tips on every gear can prevent harms to your dog's neck Safe: Dog pinch collar prongs are smooth and rounded to ensure that no harm comes to your pet while still ensuring that they will pull significantly less while walking.Designed to correct with even pressure all the way around the dogs neck to protect the trachea and other sensitive areas. Easy controll: Gentle to firm pull allows collar to communicate to dog your desired actions; Uses prongs for gentle correction. Prong collar is chrome-plated for durability and feature removable blunt-cut rubber tips on smooth and rounded prongs to prevent injury.These great training aids provide a heavy-duty yet safe alternative to standard choke chains. Ruggedly constructed of electronically welded steel for added strength. Will not rust, tarnish or break. Measures 22-inch length by 3-4/5-inch width. Prong collar for dog is the ideal training solution Prong collar is chrome-plated for durability and feature removable blunt-cut rubber tips on smooth and rounded prongs to prevent injury. These great training aids provide a heavy-duty yet safe alternative to standard choke chains. Ruggedly constructed of electronically welded steel for added strength You can remove or remove add back pongs from the collar as needed to fit your dog&#039;s neck. it is very esay to remove or add prongs, you can watch the left picture to do it. you also can use tool to remove or add it.