 Taeyeon and Jonghyun's duet "Breath" (Korean version) was the first track to be released on the 10th of February, with Jonghyun and Chen's duet "One Day" being released on the 11th, and Taeyeon's solo "Set Me Free" being released on the 12th.A Mandarin version of "Set Me Free" sung by Zhang Liyin was released exclusively online on Baidu Music on the 13th.The full EP was released on February 13, 2014.