The new Lead can be attached to a collar or harness.

The new Lead is a Dog Training Aid. It comes with instructions for you to learn a technique using the new Lead.
Follow the simple steps provided and soon your dog will be walking beside you without pulling.
It is like your dog training Instructor is walking beside you.
This Lead can be bought from Ebay with full Instructions………..
https://www.ebay.co.uk/itm/124033131270