The creation of units with product specialization is assumed to be a general criterion in the design of production systems’ structure. In relation to the existing production structures, the general research of division, i.e. research on the possibility to deepen product specialization, is especially essential and useful as it preliminarily informs about the possibility of division into smaller production units (also with product specialization). For new systems, the possibility of dividing the whole set of items (predicted for production) and workplaces into product specialization units is being examined. Assessing the possibility of dividing existing grade I production units into smaller product specialized ones or a possibility to create new units from the beginning, may be achieved on the basis of the so called division susceptibility index.