The mini knee joint has been reduced to a half of the natural size of a human knee but has kept all of the functionality of the larger knee joint models. In addition to the external anatomical structures of the knee, using the superb new knee joint cross-section mounted on the base, the medical or teaching professional now has the possibility to explain what is happening from "within" the knee joint. 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.