Black octagonal (ELSA) ring with white 5 alpha-numeric code inscription.
note 1 : 5 large letters and/or digits repeated on 4 sides (=ring number) and a code with 3 letters repeated on 3 sides (=code of ringing scheme) and small text for ring recoveries on 1 side.
note 2 : sometimes black rings could be read as dark-blue rings.
note 3 : sometimes extra codes are readable like „DEW“ which means Vogelwarte Wilhelmshaven.
note 4 : more than 10.000 birds ringed.