Tried it all, finally a solution that works!
I was given one of these to try after trying nearly every other product - from different styles of harness, pronged pinch collars, martingale collars, specialty "no pull" harness, etc.
Our 120lb+ Lab always walked me.
But now I walk him. There is NO pulling, no tugging and no straining. It took only a couple of minutes for him to accept wearing it and we were good to go.
Well worth the price (cheap by comparison to most of the other options I've tried) and much "nicer" to the dog than the pinch collar or choke chains. Easier to put on than most of the harnesses.
Don't think twice, get one and finally enjoy walks with your dog!