6″ X 8″ X 2″ Granite Surface Plate, Grade B, 0 Ledge
(Note that these are not NIST traceable.). The top surface of this plate is precision ground to achieve a high degree of flatness and the accuracy is +/-.0001″. It is a Grade B (Grade 1) plate. They are also used as a work surface for assembling, inspecting, and marking parts.
6″ X 8″ X 2″ Granite Surface Plate, Grade B, 0 Ledge
(Note that these are not NIST traceable.).