Weeekly has dropped a special video teaser for "Good Day (Special Daileee)."

In the MV teaser, the IST Entertainment girl group takes on a playful high school student concept, showing their friendly chemistry against a hi-teen setting. "Good Day (Special Daileee)" is the group's upcoming digital single, which drops on September 12 KST.

Watch Weeekly's "Good Day (Special Daileee)" MV teaser above, and let us know what you think in the comments below.