Koko-dana was created by Gengensai, based on the Sanju-dana. Koko literally means favored again. This name describes that the Sanjo-dana was Rikyu's Konomi and when Gengensai removed one shelf and changed the wood type to cedar -- the old favorite of Rikyu became favored again.
Koko-dana is 52 cm high, and each of the shelfs are 30.4 x 30.4 cm.
At the beginning of Koicha the Natsume is placed in the middle shelf. At the end of Koicha, just before carrying out the Kensui, Natsume can be moved up to the top shelf to make room for Hishaku and Futaoki in the middle shelf, as shown under.