The gentle leader is a head halter created by Premier pet products. They also make a no-pull halter and other fine products. The head halter works on the idea of a horse halter and that wherever your nose goes so do you (try it yourself) as well as the fact that the neck is one of the strongest muscles on a dog.
When I got my rottie mix he was just shy of a year old and weighed 70lbs. Wearing a choke chain he pulled my 172lbs across the length of my house (about 20yards) without breaking stride. Fortunately my first trainer insisted on using head halters and no pulls so we fixed that fast. While some dogs never really like the halter he loves his. Putting on his halter means a walk...somewhere and hats enough to get him excited.
http://www.gentleleader.com/
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