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

Alvin No. 110P Precise Triangle Architect Drafting Scale Ruler West Germany 12"

Alvin 240-P Triangular 12" Architect Scale (West Germany)

Alvin No. 110P Precise Triangle Architect Drafting Scale Ruler West Germany 12"

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

Vintage Alvin No. 241 P Engineer Triangular 12" Scale

vintage triangular Drafting Ruler Henschel co. No. 971P Germany 12" w/ case