Ruler 15 Centimeters and Ruler 6 Inches Stock Vector - Illustration of calibration, equipment: 213158272
3 Pack Two-Color Scale (inch, cm)Plastic Ruler Set Straight Ruler Plastic Measuring Tool for Student School Office (6 inch Ruler,8 inch Ruler, 12 inch ruler/15,20,30cm) - - Amazon.com
Inches to Cm Converter - The Calculator Site
Inches to cm Conversion (Inches To Centimeters) - Inch Calculator