BY2 is a duo from Singapore composed of twins Miko Bai Wei-Fen (白緯芬) and Yumi Bai Wei-Ling (白緯玲) (born March 23, 1992). Their duo band was named "BY2" after their surname "Bai" and that they are twin sisters and have a 10-year contract with Ocean Butterflies Music Pte Ltd. They debuted with their album "16未成年" on 21 July 2008. These sisters have been given different hairstyles for easy identification due to their uncanny resemblance. Read more about By2 on Last.fm.