The supplement is called Quitt, and it's only for horses who seem to need a wood fiber in their diet. For wood chewers, but it won't help Cribbers.
No Chew is a paint on topical that is supposed to taste terrible, but my horse actually does not mind the taste of it, or Cayenne pepper OR Irish Spring soap for that matter. The best thing we did was unhook the corner feeder and give him a rubber bowl to eat on the ground level.