[PennysMum]

Choke collars are usually chain (not always-- I've seen cloth ones too). They hang lax until you give a jerk on the lead, and then they tighten around the dog's neck. For most dogs, the quick snap they give is fine as a reminder to pay attention-- but it really isn't something that a dog with a breed predisposition for tracheal collapse should ever have used on them.

As far as regular collars go-- well, Penny has one, but never has a lead attached to it. It is just for holding her ID tags. I always walk her on a harness. Pressure on the neck is just a risk factor for yorkies.