Abstract: The present disclosure relates to a device, system and method for treating sleep conditions that may include positioning into the mouth of a patient a device including a lower mouthpiece, including a locating device; an upper mouthpiece, including a housing; a valve body, insertable into the housing, including a channel having a slot defined therein for adjustably receiving the locating device in the slot, and at least one passageway; a first valve portion, insertable into the at least one passageway, including a slider; and a port, including a slide guide configured to slide-ably receive the slider.