3 STEEL RULERS WITH ENGRAVED DOUBLE-FACE MARKINGS - Each ruler contain 1/ 64 inches and 1/ 32 inches gradations on one side; mm and 0.5mm graduation on the other side. DURABLE STAINLESS STEEL RULERS - Quantity: 3 x rulers, which are made of hardened stainless steel. Thickness of the rulers 6"; 0.035" (0.9mm), 8"; 0.035" (0.9mm), 12"; 0.040" (1mm). PRECISE MACHINIST SCALE - Easy to read photo etched scales don't strain your eyes; They perform well on any measuring or drawing task.