rotring - No reserve price - Mechanical pencil

Rötring trio-pen, NOS. A high-quality multifunction writing instrument for technical drawing, design, or writing is offered at auction. Unlike other standard multi-function pens that combine colored inks or a single mechanical pencil, this model stands out for integrating three different mechanical pencils into a single body ("3 Feinminenstifte in einem Halter / 3 pencils in one", as indicated on the side of the box).

Color and Finish: The main body has a very elegant matte black finish, characteristic of Rötring’s technical designs.
Grip Zone: It features a metallic grip section with a knurled texture (a rough engraving) in black, designed to provide a firm hold and prevent fingers from slipping during precision strokes.
Distinctive Detail: At the top of the body, just before the push mechanism, the iconic red ring (Rötring) stands out—the brand’s global identitary seal.
Clip: Includes a very sturdy chrome-plated metal clip to attach to pockets or folders.

The Three Lead Thicknesses
The device is designed to house three of the most standardized and widely used lead thicknesses in technical and line drawing:
0.3 mm: For extremely fine lines, meticulous details, or preliminary guides.
0.5 mm: The versatile standard thickness, ideal for writing as well as mid-lines.
0.7 mm: For thicker lines, contours, or quick shading.

How It Works (Gravity Selection Mechanism)
According to the illustrated instructions on the back of the box, the system operates via a pendulum or gravity mechanism:
Selection: At the top end of the pen body, the thickness marks (0.3, 0.5, 0.7) are printed. To activate a specific thickness, you must rotate the lead holder so that the desired number points upward (toward you) and then press the top push button.
Retract: To store the lead or change thickness, press a small quick-release button (usually located next to the clip) or operate the mechanism so the tip safely retracts back into the body.
Reload: The illustration also shows that the textured front cone can be unscrewed to access the internal independent tubes and reload the corresponding leads.
It is a highly valued German engineering tool for its practicality, as it allows changing line thickness instantly without releasing the tool or carrying three separate leads pencils.