Usage guide: The protective collar has double-lock snaps on one side of the protective collar. Secure the protective collar snugly around your dog’s neck, but not tight enough to choke them. Line up the snaps to the corresponding holes on the opposite side of the protective collar and press together. To secure the protective collar on your dog, rotate the protective collar to position the snaps at the back of your dog’s head. After the snaps are secured, attach the protective collar. Attach the protective collar to your dog’s regular collar with soft gauze or string. The protective collar should extend beyond the length of your dog’s nose. Size: Fits extra large neck size 31.12-53.34cm circumference