Dietzgen 1626 Wooden 3-Sided Triangular Ruler Scale Drafting Vintage USA 12" Woo

Vintage Architect's 12" Triangular Plastic Scale Ruler ~ Made in U.S.A.

Vintage Dietzgen No. 31626 Wooden 3-Sided Triangular Scale Ruler--for drafting

Dietzgen Wooden 3 Sided Triangular Ruler Scale Drafting Vintage 31626 USA 12"

Triangular Ruler Vintage Wood Dietzgen 31626 Architect 12” U.S. STD

Vintage DIETZGEN 1667B Excello Engineer Triangular Drafting Scale, Ruler, U.S.A.

Dietzgen 1626 Wooden VTG 3 Sided Triangular 12" Ruler Scale Drafting Vintage USA

U.S. ST'D Triangular Engine Divided Wood Ruler Made in West Germany Vintage