Davichi's Kang Min Kyung will be keeping her promise a day after making it.

Kang Min Kyung promised the members of Speed that if group Speed's song "Sad Promise" that she featured for gets into top 10 of music charts, she would buy all the members a cell phone.

Speed's song "Sad Promise" that was released yesterday is currently top 10 of MelOn chart, which means Kang Min Kyung has to keep her promise."

Kang Min Kyung said, "This is even before their debut on TV and there are many new idol groups that debuted but could not see good results on music charts, so I thought it would be hard for them as well."

But after checking that "Sad Promise" made it to top 10, she called her manager and said that she will buy them a cell phone each within this week.