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

Aluminum Triangular Architect Ruler w/Laser-Etched Imperial Drafting Scales 12"

Alvin - 30ATS - Mini Aluminum Architect Triangular Scale Ruler - NEW

Vintage Alvin Triangular Drafting Graphic Ruler, Germany, 744PM

Alvin 12" Triangular Drafting Architects Scale Ruler 247, in Case, Boxwood

Vintage Alvin No. 241 P Engineer Triangular 12" Scale & One Unbranded

Alvin 247P Metric Triangular Drafting Scale Ruler (30 cm / 11.81"). Germany

Vintage ALVIN Triangular Drafting / Engineering Rulers / GERMANY