Vintage "Mathema" Boxed Nautical Captain Fields Parallel Ruler 15inch (38cm).

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Vintage A W Faber Castell 883-Z2 Triangle Ruler With Clear Case Made in Germany

Vintage A W Faber 'Castell" Scale Ruler in case

Vintage A.W.Faber Castell 3 Sided 873c/Z4 Triangular Ruler With Case

Unique Flexicurve Drawing Tool 46cm Architecture Engineering Drawing Design

Rietz Slide Ruler 301 Denmark Vintage With Leather Case - RSPCA Middlesex/Herts