Prolapsed Lumbar Section is made of natural cast. The spine consists of the five lumbar vertebrae, sacrum, spinal cord and paired spinal nerves. A section of the sacrum shows the branching cauda equina. Also with L3-L4 dorso-lateral prolapse. 13" length mounted on base. Now included with all 3B Scientific Anatomy models is the 3B Smart Anatomy app. This app allows users to register their 3B item to extend the warranty from 3 to 5 years plus free 1 year access to the 3B Smart Anatomy app which includes 23 Anatomy lectures, 117 interactive models and 39 quizzes.