Choke chains can be dangerous
Metal training collars or "choke chains" should only be worn when the dog is being walked or being trained. They should never be left on a dog without supervision.
Training collars can be very dangerous if left on the dog. There are many horror stories about dogs trying to climb over fences and hanging themselves with the training collar. They can get it caught in their mouth. They can get their leg caught in it. They can get it caught on a protruding object and choke themselves to death. And I even had one client from my grooming shop tell me that her Irish Terrier used to like to grab her Border terrier's collar and drag him around. She came home one day and her Border Terrier had been choked to death by her other dog while playing with him.
So please, only use the choke chain for what it was made, for training. Take it off the rest of the time and keep your dog safe.
Molly