Kwon Jung-yeol was the main vocalist in the group and played the jembe, a type of percussion played with bare hands while Yoon Cheol-jong played the guitar. In 2017 it was announced that Yoon Cheol-jong would leave the band after deciding not to renew his contract due to health concerns. In July 2017 he admitted use of marijuana.
Since the debut release, they released one single Americano in 2010, and the first official album 1.0 in February 2011. The album sold over 20,000 copies which Korean music critics called remarkable considering consumers' tendency to download music online. The band also held its first concert in February 2011. On September 11, their song "Hold Me" reached #16 on Billboard K-Pop Hot 100.