Billlie have released a track preview of their upcoming collaboration project. 

'Track by YOON' is a new project by singer/producer Yoon Jong Shin. The first release of 'Track by YOON' features a remake of Yoon Jong Shin's "Patbingsu" and "Freeway Romance" sung by rookie girl group Billlie. 

In the track preview, Billlie sing a sweet and melodic tune in "Patbingsu". The second track "Freeway Romance" delivers a retro mood with a refreshing climax. 

Both tracks will be released on July 14 at 6 PM KST.