The Herm Sprenger Dynamic RS Dee prevents the bit from being pulled through the horse's mouth. It lies steadily on the tongue encouraging a positive contact with the bit and the rider's hand therefore giving confidence to sensitive horses. The mouthpiece directs gentle pivotal pressure onto the horse's entire tongue enabling precised rein aids. The fixed rings cannot slide through the mouthpiece when the reins are being pulled. It is therefore more direct compared to a loose ring snaffle.