Bundles of one hundred copper mon coins strung alongside one another for convenience of each transportation and payment. Mon coins have been holed, letting them to generally be strung alongside one another on a bit of string. From the Edo duration of Japan (1615-1868), stringed with each other coins https://financefeeds.com/jack-dorsey-silent-as-new-theory-ties-him-to-satoshi-nakamoto/