This part of ISO/TS 13399 specifies a concept for the design of tool items, limited to any kind of milling cutters with arbor hole and non-indexable cutting edges, together with the usage of the related properties and domains of values.This part of ISO/TS 13399 specifies a common way of design simplified models that contain the following:— definitions and identifications of the design features of milling cutters with arbor hole and non-indexable cutting edges, with an association to the used properties;— definitions and identifications of the internal structure of the 3D model that represents the features and the properties of milling cutters with arbor hole and non-indexable cutting edges.The following are outside the scope of this part of ISO/TS 13399:— applications where these standard data may be stored or referenced;— concept of 3D models for cutting tools;— concept of 3D models for cutting items;— concept of 3D models for other tool items not being described in the scope of this part of ISO/TS 13399;— concept of 3D models for adaptive items;— concept of 3D models for assembly items and auxiliary items.