I have mentioned and recommended the Dually halter in my previous horse training blogs as it is a wonderful training tool designed by the world-famous trainer Monty Roberts. He named it after his champion reining cow horse who he trained himself. Also it serves a dual purpose. It acts as a normal halter when you use the standard side rings or bottom ring, and as a training halter when you use the rings attached to a second noseband that slides through.
The halter should be snug, but not tight, and the schooling noseband should rest on the bony bridge of the nose, so as not to compress the airways. It is best to use a long lead rope of at least twenty feet when training with this halter to give him room as he could respond unfavorably the first time. He should never be left unattended while wearing it and should never be tied up with the training rings.
The object of training the horse with this halter is to get him to want to give to pressure rather than resist it, as is their normal instinct. When he resists the halter, it becomes smaller and less comfortable, and when he cooperates, he gets an immediate reward as it expands and becomes quite comfortable. Create an environment in which he can learn, and he will actually teach himself that it is far better to respond willingly to it than to act out against it.
Training a horse with this halter teaches him respect and will make him a lot easier to handle in difficult situations. Using a rope with a chain over/under his nose, through his mouth or over his lip or using a twitch are “quick fixes” that do not address the underlying problem that the horse simply does not trust or respect his human handlers. When you use pain to try to force the horse to comply with your requests, you will end up with a dangerous horse that will respond violently to pain.
As Monty always said, the most important part of any tack or equipment used on a horse are the hands that hold them. You can have the best halter, bridle, or bit, but with the worst hands, it will not achieve the desired results.
I wish to further his desire to make this world a better place for horses. Good luck and happy riding!