This is a charming miniature Japanese inro made from bone. Each side is engraved, one side shows a Samurai warrior with a sword and Japanese writing, the other shows a picture of a person gazing at an old tree. Japanese garments had no pockets so containers (inros and sagemonos) were suspended on a cord through the belt and would be held the other end by a netsuke, a decorative object, which was attached to the other end of the cord so that it would be held securely and would not fall through.
This is a miniature three part bone inro with a bone bead and a cord, the size suggests that it is either for decorative purposes or was made for something extremely small such as pills or something similar. It measures just 4cm long.