This is a Unshu Kamesho abacus with 27 digits, made entirely of ebony. The previous owner only used it for normal maintenance and practice. Nowadays, acquiring a new abacus made of ebony, purple sandalwood, or other precious materials requires a considerable sum. This one came from my family home (an abacus school), and I hope everyone will use it. It's also perfect for collectors. Thank you for looking.