BTOB's Changsub has shared an audio preview for his upcoming solo album.

As reported, Changsub will be releasing his first album 'Mark' prior to his military enlistment. In this audio snippet, Changsub sorrowfully roams around different locations with a winter setting. The ballad-based album presents another mellow side to Changsub as the lead vocalist of BTOB.

Listen to a snippet of all six tracks in the video! 'Mark' will be fully released on December 11th.