General Tools 820 Metal Marking Gage With the General Tools and Instruments 820 Metal Marking Gage, Single Bar you can easily trace the edge of a flat surface for ripping and cutting The steel bar features an engraved, graduated ruler for making accurate measurements The needle point scriber easily marks wood, plastic, hardboard and other materials The needle point is ultra fine for extreme precision marking Nickel plated, this gage is constructed for consistent use and durability