The Eight Extraordinary Vessels also known as the Eight Singular Distribution Vessels include: Du Mai (Governing Vessel), Ren Mai (Conception Vessel), Chong Mai (Thoroughfare Vessel), Dai Mai (The Belt Vessel), Yang Wei Mai (Yang Linking Vessel), Yin Wei Mai (Yin Linking Vessel), Yang Qiao Mai (Yang Heel Vessel) and the Yin Qiao Mai (Yin Heel Vessel). They have a neurovascular basis and act as a capacitance system, capable of receiving an overflow of Blood. The Du Mai represents the vertebral venous networks and dural venous sinuses. The Ren Mai is the venae cavae and its tributaries. The Chong Mai is the only arterial structure among the eight, the aorta. The Dai Mai is correlated with the subcostal nerve, artery and vein and most likely the hypogastric nerve as well based on its indications. The subcostal veins that encircle the body arise from the Du Mai (GV) at the ascending lumbar veins, near the second lumbar vertebra. The Yang Wei Mai, Yin Wei Mai, Yang Qiao Mai and the Yin Qiao Mai are pairs of superficial singular vessels which relate to the complex networks of interlacing venous channels connecting the pelvic limbs and head in humans. Converting notions of these vessels from the currently abstract, poorly understood entities into anatomically recognizable vascular structures furthers the ability of veterinary acupuncture researchers to identify their counterparts in non-human species.