TGL 31034-1 by Peter Wiegel is a free technical sans serif with very light, nearly monoline strokes. Tall, narrow forms recall standardized drafting letters, with rounded bends softening the geometry. Open shapes and clipped diagonals keep the design precise and industrial.
As a technical title, it can make diagrams and exhibition graphics feel engineered. The restrained construction also suits architectural publishing and electronics branding. Repeated rounded corners connect these applications with schematics, tubular icons, and line drawings.
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This font was used for technical drawings in East Germany and now includes Cyrillic letters.