If you would describe your horse as something with the following;
Never really seem to appreciate the bit you have.
Refusing to soften down into the bit
Needs to seek the bit without getting stiff.
FEI & EA Dressage Legal for dressage riders &hrcav
Alexander's anatomically shaped mouthpiece 45° twisted french link is following the natural contour of the tongue. Together with the taste of sweet iron, this bit accepted even by very picky and sensitive horses.
This middle piece works well on a horse who uses his tongue to push against the bit and therefore taking control.
When taking the reins, it will give both bar and tongue pressure making the horse come back with a lighter feeling in your hands.