Timber Framers Guild Forums General General Forum Questions Folding ruler Klein and sons incorporated Chicago

Do you have any information on this ruler ?

#905-6. (Model number)
Brass bound folding ruler.

Like this?

http://www.kleintools.com/catalog/folding-rules/wood-folding-rules-extension

Zig-zag rules are very common and as you can see in the current catalog. Such rulers were I believe a German invention by the founder of the Stabila level company in the nineteenth century.