Vintage Alvin Triangular Drafting Graphic Ruler, Germany, 744PM

Vintage Alvin Triangular Drafting Graphic Ruler, With Case, Germany, 744PM

Alvin 742 PM Triangular Drafting Engineering Scale Ruler Made in Germany

Alvin 744PM Drafting Engineering Triangular Square w/Case West Germany Vintage

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Vintage Alvin Triangular Drafting Graphic Ruler, With Case, Germany, 744PM