The radial veins run the length of the forearm just below the elbow, and follow the path of the radial bone. Their path is also somewhat comparable to the radial arteries. These veins assist in draining oxygen-depleted blood from the hand and forearm. In this process, the blood flows to the brachial vein and eventually makes its way back to the lungs for resupply with oxygen, and then to the heart for recirculation. This is an opposing process to the radial arteries. These arteries deliver oxygen-rich blood to the muscles and other components of the forearms. The radial veins are venae comitantes. As such, they run parallel to their opposing arteries. This makes for a more efficient circulatory system. This is usually found in the extremities of the arms and legs. However, unlike the radial veins, not all components of the venal system work as venae comitantes. For example, this complimentary relationship is not found with the subclavian artery and vein, or the axillary artery and vein.