3 Different Measuring Range Rulers] 15cm, 20cm and 30cm are suitable for different measuring jobs. Often used by carpenters, drywallers, architects, students, teachers, offices, DIYers and more! [Industrial Grade Stainless Steel Ruler]Stainless steel, prevent rust and corrosion. The office ruler is made of durable stainless steel that is unbendable but somewhat flexible for long-term use; the marks are slightly recessed in the metal so they won't rub off over time. [Conversion Table for Quick Calculations]There is a conversion table on the back to help you calculate measurements in other units; the measurement marks start from the edge of the rule, which is easy to use. [Polished and Thicker Sides]More polishing and polishing process than other suppliers to ensure that the inner edge is not sharp and safer for you and your kids. The ruler has a smooth surface without burrs; one end is square and the other is round with holes for easy hanging. Color: silver Packing list: 3pcs