Any maintenance and repair tool box is never complete without rulers. For use in homes, workshops, or even in warehouses and manufacturing facilities, straight edge rulers and engineers rulers can come in handy for spot and speedy size measurements. Engineers rulers can be folded for added portability. On the other hand, straight edge rulers can be used to create and trace straight lines. Rulers are graduated in Metric system side using millimeters, centimeters, and meters while the English system side is marked in 1/16ths.