Buddy uses a snaffle bit on Zum with 3 inch rings and a 5 inch mouthpiece. He tells me that this snaffle bit is intended to control, reinforce and refine lateral flexion or sideways pulls of the reins. He uses only one active rein at a time. It teaches Zum to move his head and hindquarters to the side. This bit is not the kind of bit to pull on with both hands to stop the horse. He says that there is a perfect bit for every stage of a horse’s training.