A hardened stainless steel metric ruler from Matsui Precision Manufacturing company that would make the perfect gift for any crafts person in your life.
It comes with a yellow vinyl slip and conversion table engraved on the reverse.
Niwaki says that Japan were one of the original 17 signatories to the 1875 Treaty of the Metre in 1875. That's 110 years in front of the UK. So we'd say this ruler is something you can trust.