HIGH QUALITY BRAND NEW EASY TO USE The engineering scale ruler is made of solid, lightweight aluminium that is easy to use for blueprints or any professional or educational project. This triangular-shaped 12" scale ruler is used by architects and engineers to draw precise scale drawings. For long-term use, the triangular scales are made of high-impact aluminium alloy steel with precise graduations etched on them. Architectural and engineering scales are both available in triangle scales. These rulers make line art, drafting, measuring, and educational projects much easier. It's ideal for architects, engineers, students, and contractors who want to deliver exceptional results.