The Port allows enough room for the horse's tongue to fit comfortably under the flattened area of the port. Relaxation and chewing are a common reaction to this bit which is perfect for horses that won't tolerate tongue pressure who often react with excessive head shaking. The Swales is a unique design similar to a Pelham but removes the poll pressure as the bridle cheeks attach to the loose cheek rings that float on the bar of the bit. The minimal poll pressure emphasizes the amount of pressure on the lower jaw from the curb chain causing a lifting action. The bit is used on horses who are very heavy on the forehand and tend to drive downward instead of opening up the shoulders and moving off the forehand. This bit is meant for experience riders.