4.2. Every device for indirect vision shall possess, on at least one of the main components a space large enough to accommodate the approval mark, which shall be legible; this space shall be shown on the drawings referred to in Annex 1. The approval mark shall also be legible when the device is mounted on the vehicle with exception of camera-monitor devices as defined in paragraph 2.1.2. Other components of the device shall bear a means of identification. In the case of limited space for the approval mark(s), other means of identification that link it to the approval mark shall be provided. a0c0