Okinawa Sanba (castanets) with Raden (mother-of-pearl) inlay

Okinawan Sanba is a traditional percussion instrument made of three wooden boards (such as ebony or oak) connected by strings, essential for Okinawan folk songs and Kachāshī (celebratory dances). It is also called the Okinawan version of castanets and is characterized by playing rhythms with one hand (making a kachi-kachi sound).
This is a rare piece with mother-of-pearl inlay.

It is unused, but has been stored at home and had minor scuffs from the time of purchase.

The material is unknown.