I think it came from an old camera. A fine strong string/cord with a quick connect clip. It is looped/tied at the D ring that holds the battery compartment on my 590 and then attached to a carabineer clip to a spot behind the unit and in front of the reservoir. Two ways to unhook when needed. The 395s have more of a reputation for coming unmounted than the 590s but I wanted to be ready it ever does pop out.