Super Heavy Beta BioThane leash.
The regular 6' leash has a ring in the handle to allow you to connect it over your shoulder when not in use.
The configurable Jaeger Leash allows multiple options, including over the shoulder, tree tie out, full 8' leash etc. A favourite among dog handlers!
Check cords have no handle, just a solid brass snap at one end, ensuring it does not get caught up while your dog is dragging it.