kiiro 5 was one of the first three Hello! Project shuffle units, based on the color yellow. Their song, Kiiroi Osora de BOOM BOOM BOOM (黄色いお空でBOOM BOOM BOOM) is a basically your standard H!P fare of pop. The song was released on 8cm CD single (EPDE-1071), and was also released on the first Pucchi Best (Petit Best) album, subtitled The Ki Ao Aka.
The members of this groups consisted of Abe Natsumi and Yasuda Kei of Morning Musume, Heike Michiyo, Kimura Ayaka of Coconuts Musume, and RuRu of T&C Bomber. The leader of the group was Abe Natsumi.
When T&C Bomber broke up, RuRu left the group and her parts were given to Morning Musume member Kago Ai.
This song was covered on Heike Michiyo's album For ourself～Single History and Abe Natsumi's album Hitoribocchi. With both versions there is a rap at the beginning of the song. The raps are different for both versions.