Kassy and MAMAMOO's Solar have revealed a preview of their collaboration song "A Song from the Past".

The two talented vocalists are releasing an emotional ballad about memories from the past, and the teaser clip above gives you a sneak peek of the melody and and Kassy and Solar's beautiful vocals. Fans are already excited about the unexpected collaboration.

Kassy and Solar's "A Song from the Past" drops on January 16 KST. What do you think of the teaser?