 Also, it's a nod to SS501's Official fanclub, Triple S.

The group was set to have a concert at BLUE SQUARE Samsung Card Hall on March 19 and 20, 2016 entitled ""2016 Double S 301 CONCERT〈U R MAN IS BACK〉IN SEOUL"".This marked the first major event held by SS501 since their departure from DSP Media in 2010, and their 2013 concert.Double S 301 held its comeback showcase at Art Hall of Lotte Card Art Center on February 15 at 8pm KST, and released their official debut mini-album ETERNAL 5 on the following day.