Mitutoyo182-171 Wide Rigid Steel Rule, 600 mm Range

Good quality ruler

This Mitutoyo ruler is not cheap but it is worth the price. I needed a sturdy and accurate metric ruler that I could read down to about 100-200 microns over distances up to about half a meter. This ruler fits the bill nicely. It is made of stainless steel and is thick enough to stay straight. It can be bent slightly to follow a gentle curve. Don't waste your time on cheap imitations or plastic rulers that are not accurate and have scales that don't start at the end of the ruler. This one does, and it makes measuring from a flange very simple and more accurate.