Alvin 3 Sided Engineer Scale No 119 PC Triangular Drafting Ruler W-Germany

Dietzgen 12" Triangle Ruler 1667-BG made in Germany and Graph Paper made in USA

Vintage Keuffel & Esser Paragon 1631P Triangular Drafting Ruler READ & PHOTOS

Vintage 12" Wooden Desk Ruler with Brass Edge - Made in USA - Drafting Tool

(2) Dietzgen Excello Drafting Ruler 1590 Vintage 12" Length USA Made 1590, 1593D

Lutz - Triangular Ruler - 12 inches - Drafting Architect

Vintage Dietzgen Architects' 12" Triangular Scale Ruler 1683B Excello

Dietzgen Drafting Ruler 1517P Vintage 12" Length USA Made #1708