12" Triangular Scale Ruler Engineer 1:10, 1:20, 1:30, 1:40, 1:50, 1:60 BAMBOO CORE This is our bamboo core version of http://www.amazon.com/gp/product/B00C3AFA6Y. This is an Essential tool for engineers. Compare to Staedtler and Helix - these are higher quality with inked grooves.. NOT just printed on. 12 Inches Triangular divided 10, 20, 30, 40, 50 and 60 parts to the inch. Red Green and Black colored grooves, Engraved markings and notches. NOT just painted on!!! Hi Quality Bamboo Core Made in Japan