This is how a set of car keys looks like: 1 - ignition key; 2 - electronic learning key of the immobilizer; 3 - electronic working keys of the immobilizer; 4 - key for door and trunk locks.
The key number is marked on the ignition key flag, to keep the number secret, cut and remove the flag.
The key number of the door and trunk locks is stamped on the key itself, so as not to change the locks in case of loss of the keys, new keys can be ordered from the factory by their numbers.
The red electronic key for the immobilizer is training, two black electronic keys are working. More details on the use of immobilizer keys are described in section 9 «electrical equipment» in subsection «car anti-theft system (APS)».