The popular male vocal group SS501's third single "Lucky Days," which was released in Japan on June 18, climbed to the number two spot on the Oricon Daily Single Chart on the same day.

What makes the feat so significant is that all of the songs in the single album were written by a Korean composer.

The album includes the title song "Lucky Days" written by composer Hwang Seong-je and "Summer Blue" by Lee Joo-hyeong. The Japanese version of "A Song for You," a number which had previously only been released in Korea, is also included in the group's latest single.

SS501's management agency DSPent said the group will focus on its promotional activities in Japan until early August. Member Kim Hyun-joong, who makes a regular guest appearance on "Just Married," a popular segment of "Sunday Night Entertainment," will travel back and forth between Korea and Japan.

SS501 plans to hold three concerts from July 12 to 13 in Tokyo and two concerts from July 16 to 17 in Osaka.