Almost all bridles brush over the temporomandibular joint (TMJ), this is the joint where the lower jaw connects to the skull. Any movement the horse makes with its mouth, causes motion in this joint. This means most bridles cause friction when the horse chews, licks or relaxes its jaw. The FaySport bridle is specially shaped around this joint, to prevent friction. This encourages the horse to chew, lick and relax its jaw. A relaxed jaw is a requirement for the horse to be on the bit correctly.