The Comfort bar is characterized by a slight bow designed to fit anatomically correct to rest equally on the tongue and bars to offer more room & mobility for the tongue. When pulled upon this bit will apply pressure evenly throughout the mouth eliminating any lateral squeezing of the tongue and bars. The Comfort bar is ideal for young and sensitive horses as well as satisfying the needs of many different horses. The US Tandem is to be used with one set of reins. The pressure is distributed evenly between the horse's nose, lower jaw and poll. More rein action puts more pressure on the bars of the mouth. Suitable for horse's that are very sensitive in the mouth but can't be ridden with a Hackamore only. The US Tandem has black flexible tubing for the nose band instead of bright blue nylon rope found on regular Tandem.