Third-class standard metal line scale (also known as the Geneva feet) is a precision carved metal thermometer reading with a magnifying glass and a ruler. Often used in mapping the job profile chart checking point, control and coordinate the network distance between the point at the national level as a standard measurement of the Specification standard ruler ruler for checking purposes. Other sectors are also widely used as a measure of professional and straight-line distance measurement and characterization and other uses. As a third-class standard metal line scale high-tech, innovative new products, the twenty-first century, China's independent intellectual property rights, the collection of modern science and technology, fully automated machining centers production technology, using laser-scribed line engraving, marking and map reading selection type. Products with high accuracy, high stability, high-definition, engraved line width, line spacing precise moment consistent with the law of the difference between the linear curve movements, no sudden jump, accidental error peak value, groove vertical standards, foot stiffness Well, type variable rate, good flatness, significantly higher than the precision index JJG71-2005 standard promulgated in 2005, with the world advanced level. The main instrument specifications: 1, the instrument Dimensions: Length 1050mm × width 38mm × height 63mm 2, Instrument Weight: 3Kg 3, Muxia dimensions: length 1080mm × width 74mm × height 82mm 4, a full weight: about 5.5Kg 5, m Indexing ruler length: 1020mm 6, dividing the value of Michi: The two ramps are 1mm and 0.2mm (estimable read 0.01mm) 7, Magnifier Magnification: 7x 8, dividing the value of the thermometer: 0.5 ° 9 not straight edge bevel edge of the meter stick ≤0.1