This product made of fine quality, use manganese steel, can be used to thread verification, very practical in life and work. Come on and try it. Features: Each size has a nut and bolt checker on the same gauge, you can clearly see it. This product is a inch and metric thread checker, an accurate and easy-to-use thread identifier for nuts and bolts. The product is small and easy to carry. You can take it wherever you want without occupy much space. You can attach them on to a wire loop to make them easy to carry. Size: inch(14): 6-32、8-32、10-24、10-32、1 / 4-20、1 / 4-28、5 / 16-18、5 / 16-24、3 / 8-16、3 / 8-24、7 / 16-14、7 / 16-20、1 / 2-13、1 / 2-20. Specifications: Material: steel Color: black+silver Size: inch(14): 6-32、8-32、10-24、10-32、1 / 4-20、1 / 4-28、5 / 16-18、5 / 16-24、3 / 8-16、3 / 8-24、7 / 16-14、7 / 16-20、1 / 2-13、1 / 2-20 Package size: 165 * 150 * 30mm / 6.5 * 5.9 * 1.2in Package weight: 322g / 11.4ounce Packing List: 1 * Thread Checker