This illustration-based paper presents and account of Italian History on the collections mechanism models that were used and still can be used in design, teaching, and research activities not only on research and development of mechanical systems. A conceptual procedure is outlined for the development and use of mechanism models mainly at reduced scaled size. Main Italian collections of mechanism models are introduced with their historical values and current status. Those examples are reported also to show the value of Cultural Heritage that mechanism models and corresponding developments may have as worthful for preservation and understanding of past achievements in mechanism design and its application even in other frames.