Features Bearing Steel: Thickened bearing steel measuring exterior, and is wear resistant, having long service life Carefully Constructed: With Exquisite workmanship, clear laser calibration and accurate readings High Accuracy: Built in force limiter in the measuring tool spindle to ensure accurate repeated readings Ideal Measuring Tools: Used to measure the outer diameter of high accuracy, products and precise parts Carefully Crafting: After beening carefully crafting, not only having a classic appearance, but also has a high cost performance Specification: Item Type: Outside Diameter Micrometer Material: Bearing Steel Storage Box Material: ABS Measuring Range: Approx.0-25mm / 0-1in, 25-50mm / 1-2in, 50-75mm / 2-3in Measurement Accuracy: Approx.0.01mm / 0.0004in Purpose: Measuring the outer diameter of high accuracy products and precise parts Package List: 3 x Outside Diameter Micrometer 2 x Standard Calibration Tool 1 x Special Tool 1 x Storage Box  Note: 1. When measuring, stop using the knob when the micrometer screw is approaching the object to be measured, and use the fine tuning knob instead to avoid excessive pressure, which can make the measurement result accurate and protect the spiral micrometer. 2. When reading, pay attention to whether the half millimeter engraved line on the fixed scale has been exposed. 3. When reading, there is an estimated number in the thousandth, which can not be thrown away casually. Even if the zero point of the fixed scale is exactly aligned with a certain scale line of the movable scale, the thousandth should also be read as 0. Package List 3 x Outside Diameter Micrometer 2 x Standard Calibration Tool 1 x Special Tool 1 x Storage Box