This Aluminum Straightedge is an excellent addition to my toolbox. As an industrial engineer, it is essential to have precise and sturdy measuring tools to get my job done right. My tests showed that it had a minimal variance compared to my other straight edges. The material is durable and the black markings over the silver background make it easy to read measurements. Its only drawback is that it is a bit heavy, but that is a small price to pay for its accuracy and durability. Highly recommended for anyone in the industrial and scientific field. .