The EZ Control bit can not bend backwards, which means that pressure is distributed equally an the bars of the mouth, and the bit does not wrap around the lower jaw.
The free sliding rings of the Loose Ring Snaffle enable the horse to adjust the position of the bit in his mouth. This tends to make the horse relax his jaw and chew the bit, thus encouraging the horse to accept the bit. When picking up the reins the rings move so that the bit is automatically positioned correctly. Young horses or inexperienced riders should always gain experience with a loose ring snaffle before trying out a D-ring bit or other bits.
The Copper promotes better acceptance because it encourages the horse to chew, thus enhancing the saliva production.