My horse is currently using a Happy mouth mullen mouth bit. It actually cut the corner of his lip, it may have been to big for him. He's usally uses a 5" but I put the 5 1/2" one on.
He also throws his head down when we standing still. And if I try to get him to bend from his poll at the trot he will fling his up in the air.
I need a corrective bit that would quiet his head while riding.