Dark blue ring with a white 2 alpha code (on one tarsus) and blue ring with geolocator (on other leg).
note 1 : Norwegian metal/steel rings are used.
note 2 : rings are dark blue with white inscription: 2 letters. Starting letters are C, E, H and Z.
note 3 : project in Slettnes, Norway
note 4 : in 2014, adults were equiped with geolocators attached to blue rings. In these birds, the metal ring is on the left tibia, the colour ring on the left tarsus, and the logger/blue ring on the right tarsus.