Stainless ruler 12''/ 30 cm.
Not so common these days, there's just nothing quite as precise as a steel ruler. Ours defines length in both U.S. Standard and Metric terms, as shown in our photograph. No guesstimating, no flip-flop edges, no splinters here! Vermonters like to say "...damn straight", when speaking in a no-nonsense manner. I suppose it applies here too.