This is a dog choke chain from HS (Herm Sprenger). Purchased for puppy training. It didn't suit my dog, and it was only tried on, so it's unused. ※※Regarding size selection, usage rules, and precautions※※ Please be sure to check the official website, authorized dealers, or retailers before purchasing. We are not responsible for any issues. Size: Thickness approx. 1.6mm / Length approx. 30cm