I had a pulling issue and a trainer taught me a very effective method. We used a regular nylon slip lead. Any time the dog started pulling, I would call his name once and start walking backwards. There was no correction jerk on the lead; I simply walked backwards with lead in my hand. He always came to me and then I rewarded him. He learned to pay attention to me and then we could walk on a relaxed lead. It might take a little while and I still remind him once in a while. He was a bit nervous and bringing him to me and rewarding convinced him that everything was okay. Save your money.

Training to walk on a loose lead is the best solution. But if you want a gadget to help you train, I suggest a no-pull harness. The leash attaches to the front of a dog's chest. Premier makes a no-pull harness. I think the Freedom No Pull harness is well-made and effective in
stopping pulling with a minimum of training.