This study is intended to include patients with a Thoracic Aortic Aneurysms (TAA) or Penetrating Atherosclerotic Ulcers (PAU) and assess and evaluate safety and performance data of the Relay Pro Stent-Graft System. A TAA is a weakening and bulging of the thoracic aorta, which is the body's main blood vessel that carries blood away from your heart to all parts of your body. A disease called atherosclerosis, in which fatty material accumulates under the inner lining of the arterial wall, generally causes true aneurysms. PAUs are lesions associated with aortic wall thickening and appear similar to saccular aneurysms (sac-like bulging) on x-ray. If left untreated, an aneurysm or ulcer can enlarge and rupture, causing injury or death.