Features: This clear triangular ruler set (15cm & 20cm) delivers precisely measurement with its geometry triangular designs, featuring clear acrylic construction that eliminates visual obstructions during technical drawing and geometry drafting tasks. Crafted from shatterproof plastic, these clear triangular scale rulers combine light weight portability with enhanced safety compared to glass/metal alternatives, maintaining structural integrity even with frequent classroom use. Suitable for school students and STEM educators requiring multifunctional measurement tool for geometry classes, physics experiments, and math exam preparation. Perfect for classroom geometry teaching demonstrations, architectural sketching practice, and science drafting project. The waterpoof plastic construction ensures safe daily handling while supporting learning environment, with beveled edges preventing smudges on technical drafting and engineering drawing. Specifications: Component: Plastic Color: Clear Measuring From: 0-15cm; 0-20cm Weight: Approx. 30g Package Includes: 1Piece 15cm ClearTriangular Ruler 1Piece 20cm ClearTriangular Ruler note: 1.Please allow 0-1cm error due to manual measurement. Be sure you donot mind before bid. 2.Due to difference between different monitors, the picture may not reflect the actual color