Inch (standard) and centimeter (Metric) nut and bolt thread detectors. 34 screw specifications: 15 public system +19 standard nuts and bolt sizes, the edges have inches and centimeters, which can quickly identify the size and length. Adding 8 dimensions of diamonds 4mm, 6mm, 8mm, 10mm, 12mm, 14mm, 1/4inch, 1/2inch to help you quickly and accurately determine the screw size, and recommend the drill bit or tap size required for screws. Industrial grade: Heavy solid solid 6061 aluminum alloy fuselage (CNC processing, anode oxidation surface, 6mm, 2.78 pounds), durable SUS304 bolts, and high processing accuracy. Extensive recognition range: 15 public size: x 0.7 to M16 x 2.0, 19 standard size:#6-32 to 3/4-10 fine, length measurement: 0-15cm/0-6 inches. Quickly identify and measure. There are 2 pre-drilled installation holes that can be easily hung or fixed in the toolbox. Colour:Red Material:Metal Package Contents: 1 * Bolt Thread Check Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.