This is an obi fastener made of genuine coral and genuine pearls (4.5mm diameter). My grandmother, who was born in the Taisho era, kept it carefully. Width: Approximately 4.8cm Height: Approximately 2.0cm Thickness: Approximately 1.0cm Inner dimensions of the obi fastener金具: Approximately 1.1cm I removed the ribbon for the photos, so it was probably unused.