Sandeul released the music video teaser for the title track "Summer Day Summer Night" of her new album "Thinking EP.1" on Aug. 4 through the official SNS channel of her agency WM Entertainment.

In the teaser video released, Sandeul shows off her fresh and fresh charm against the backdrop of Jeju Island on a summer day.

 The new song "Summer Day Summer Night" is Sandeul's self-composed song, featuring Sandeul's soft, warm voice in summer nights.