Leessang and�YB have released their new collaborative track "Mad Man"�for their joint concert!

According to�Leessang Company, "The song was originally only meant for the concert, but they recorded the song because fans have given so much support to the joint concert. It's a song full of energy that asks fans to have some crazy fun with them." The two bands have already collaborated with "Run" and "Someday".

The lyrics are by Gary, while Gil and Yoon Do Hyun provided their vocals for the song.

In related news, Leessang and YB's joint concert will be going on from December 23rd through the 25th, and the 29th.