Plastic Ruler, Straight Ruler, 2PCS Clear Acrylic Ruler, 12 Inch Rulers with Centimeters and Inches, Measuring Tools for Student School Office - - Amazon.com
English-Metric Ruler 15cm (6") – Arbor Scientific
Ruler 12 inch, Clear Plastic 12 inch Ruler, Apply to Rulers for Kids and Office Use Measuring Tools, Transparent Metric Straight Ruler, Ruler with Inches and Centimeters, Ruler Set Pack of 2 - - Amazon.com
CenterPoint Straight Edge Rulers - Center-Finding | US Tape