Extra wide Cuban-style designer chain makes this the best pitbull, mastiff, or other large dog collar around! It’s made of solid stainless steel, NEVER tarnish, rust, or irritate your dog’s skin. Training your dog is easy with our chain training collar. Size Measuring: Please use a soft measuring tape to measure the circumference of the dog’s neck or the widest part of the head. And the dog chain is better 3-4 inches longer than the dog’s neck size. For example: the dog’s neck size is 18inch, the suitable dog chain size is 22inches Note: Please Make sure for the right length size you purchase.