| 2.2. | A type of "retro-reflective device" or retro-reflective material is defined by the models and descriptive literature submitted with the application for approval. Retro-reflective devices can be considered as belonging to the same type if they have one or more "retro-reflecting optical units" which are identical with those of the standard model, or if not identical are symmetrical and suitable for mounting one on the left and one on the right side of the vehicle, and if their other parts differ from those of the standard model only in ways not affecting the properties to which this Regulation applies. A change of colour of the retro-reflective materials of the Classes "D" and "E" does not constitute a change of type. | a0c0 |