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Dimensional lumber tape measure
(slrpnk.net)
I hope it’s not against the rules here, just saw this woodworking related xkcd that I enjoyed and thought it might be appreciated here:)
Lee Valley used to sell a blank tape measure, for pure, real-valued metrical madness.
Basically a storey stick.
That's the idea, but significantly more expensive than a scrap piece of 1x4.
Plus for actual accuracy I'd want to score it.