There are tiny tacks in the surface of the ruler, which insert into holes on the opposite side for stability when closed. See close up photo. It looks like a bit older version of the 268 than others I have seen, with no patent mark, no manufacturer mark, and no Made in USA.
Inside marked “Stanley Rule and Level Co. / New Britain, Conn. Warranted / Box Wood. All 3 pins are present. There is a tiny bit of tear-out around
Stanley #60 Carpenter’s 24″ double-arch brass-bound boxwood folding rule
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This vintage folding ruler, model No. 268, is a classic tool for any DIY enthusiast. With a tape length of 24 inches and made from high-quality wood,
Vintage No 268 Folding Ruler 24 Wooden Boxwood Brass Tips
wood folding ruler 24 - warranted boxwood - tools - by owner
Antique Folding Ruler
Vintage No 268 Folding Ruler 24 Wooden Boxwood Brass Tips
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MASTER RULE #268 Vintage Folding Pocket Ruler 24 Four Fold
Stanley Folding Ruler
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ANTIQUE FOLDING RULER Wood Brass 24in £6.74 - PicClick UK
Stanley Boxwood and Brass 24 Inch Folding Ruler – critical EYE Finds
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