This low ported barrel mouth provides plenty of room for the horse's tongue to pass underneath, and when engaged does not rotate onto the tongue. The center barrel has limited movement to prevent the bit from scissoring down into the tongue or up into the palate. The copper roller provides some movement helping to pacify the nervous horse.
Modified Billy Allen
No-Pinch cheek style
Copper roller center piece
Stage B (Transitional - Switching between neck and direct reining)