Had to google it. Looks like an elaborate & different version of an 'overcheck'.
I don't get why the headpiece is like that - ear holes, rather than regular poll & browband. & it appears the 'aircraft cable' may run underneath it & that's all that is 'activated' - so sharp, thin pressure over the poll - no thanks, too much risk of injury to the horse! Also appears that there is no place for a bit or bosal to be attached, so if you want to ride in it, you'd need another bridle over the top(?)
If your daughter rides with a bit, an easier, less convoluted option would be to just run a cord from the bit ring, up through the poll piece & back to the saddle D(or horn of a western). Long enough to allow freedom of movement, short of putting their head right down - also a good option for people(esp little people) who aren't strong/consistent enough to stop their horses eating grass on the trail.
But first & foremost, also agree with those who said try to work out & address *why* the horse bucks, rather than just trying to tackle the 'symptom'. If the horse is bucking from pain/frightened, then while you might lessen the bucking with a piece of tack, her reactions are likely to come out elsewhere, be only temporarily 'fixed' or she will 'learn helplessness' and just be forced to put up with the pain, to her physical detriment.