Suitable size: it includes 4 different ranges (0-25mm, 25-50mm, 50-75mm, 75-100mm) for your choice Precision machinist tools: they have extremely high precision of 0.01mm, which can provide accurate readings Premium Quality Outside Micrometer: Made of very durable good hard carbide Note: Please check if it has been calibrated before use 0-100mm Outside Micrometers - Precision Machinist's Tools Measuring Ranges: 0-25mm/ 25-50mm /50-75mm/75-100mm Precision: 0.01mm High quality materials: it is made of very durable good hard carbide Instructions: 1. Wipe the test object and handle it gently when using the micrometer; 2. Loosen the micrometer lock device, calibrate the zero position, and rotate the knob to make the distance between the measuring anvil and the micrometer screw slightly larger than the measured object; 3. Hold the micrometer ruler with one hand, place the object to be measured between the anvil and the end of the micrometer screw, and turn the knob with the other hand. When the screw is close to the object, turn the force measuring device until you hear a click. Gently twist 0.5~1 circle; 4. Tighten the locking device and you can read it. Attention to maintenance: 1) Handle gently 2) Wipe the measuring anvil and differential cylinder to avoid the influence of chip powder and dust 3) Separate the measuring anvil and tighten the fixing screws to avoid rust due to prolonged contact. 4) Do not put them in a place with high humidity and large temperature changes 5) It is forbidden to use a micrometer to measure running or high temperature objects 6) It is strictly forbidden to use a micrometer as a vernier caliper or a hammer to hit other objects. Note: Due to the light and screen setting difference, the product's color may be slightly different from the picture. the image. As the manual measurement is different, please allow slight differences in the size. Shipping quantity: a set of 4 pieces