JETRIDE, 2 Way Ballpoint Pen, Easily Draw Straight Lines without a Ruler, Ball Point (0.5mm / 0.7mm) (Black) : Amazon.in: Office Products
This small metal trinket lets you draw straight lines without a ruler - Yanko Design
Constrained Ball - Concept Line Maker and Measurer - Make:
Woo designed a pen attachment that can help you draw straight lines. Zalled the"Constrained / okay guy :: invention :: line :: pen :: funny pictures / funny pictures & best jokes:
REVIEW: GOOD MADE BETTER PENWELL TRAVELER PEN STAND | The Pencilcase Blog | Fountain pen, Pencil, Ink and Paper reviews
Entry #21 by engineerhaitham2 for Design of a new object/product - Modified "Constrained Ball" | Freelancer
Design of a new object/product - Modified "Constrained Ball" | Freelancer