Acts on the tongue, bars, and poll. Stronger lateral effect due to the center connection of the mouth piece to the cheeks. Quicker action due to center fulcrum. Cheek pieces provide correction to resistance to the direct rein. Functions as a snaffle with light rein pressure. Functions as a mullen mouth as rein pressure increases. No nutcracker effect or palate pressure. To protect the horse from possible pinching, use one size larger than your snaffle.