22-part skull with didactic bone color features a natural cast replica that can be disassembled into its 22 individual bones. The individual bones connect by means of inconspicuous, stable connectors attached at slightly simplified skull sutures. The bones are depicted in 9 didactic colors and each pair of bone plates has the same color. 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.