Stakeholders who are part of the development process of a new Product-Service System (PSS) could use interactive prototypes during meetings to exchange different point of views. Based on the findings of a conversation analyst and the reflections of a design researcher we compared three explication techniques of how a prototype was involved during such a meeting (for pointing and manipulating, for demonstrating its function and for imitating and/or demonstration through body movement and gesture) with the phases of a co-reflection session (exploration, ideation and confrontation). We found that the prototype was especially useful during the exploration and confrontation phases. Pointing and manipulating helped to make reflections concrete, made it easier to propose small design changes and helped the participants to reach common goals. Interactive prototypes do have their limits, during the ideation phase the prototype did not play an important role.