I used martingale collar for my dog when we walking or even when I want training my dog. That collar doén't make dog hurt like prong collar. When my dog pulls, the collar will automatically get tighter around their neck, correcting their moves without choking them. I used this collar, Country brook petz martingale heavy duty nylon collar, sizes between 18 inch and 26 inch neck and this collar is also made of stainless steel. It has a lot martingale collar, I read review in dogtelligent before buying. If you interested in that collar you can read in there.