About this item [4 measuring methods and safety]: Digital calipers can be used to measure inner and outer diameters, depths and steps. The pins of the caliper are made of plastic, so there is no short circuit when measuring the battery or inside. Contact with the positive and negative poles. The safety is higher than that of metal calipers. [Measurement accuracy]: measurement range: 0-6″/0-150mm; resolution: 0.01″/0.1mm; accuracy: ±0.2mm/0.01. A perfect and accurate caliper measuring tool, suitable for home/jewelry/DIY measurement, please pay attention. This caliper is not suitable for professionals with high technical accuracy. [Inch/mm conversion]: Use Simhevn digital caliper to switch freely between inches and millimeters. The switching function of the two units can meet different needs. It is more convenient and widely used for measuring the value you want. [LCD and automatic shutdown]: High-quality and trustworthy digital calipers, LCD display screen reading is more convenient, quick and easy to get accurate results, open automatically turn on, and automatically turn off after 5 minutes of use. It is powered by a battery and includes a pre-installed battery and a spare battery. [Zero reset function]: Intelligent design, you can easily reset to zero by pressing the “Zero” button at any position of the measurement, and start a new measurement. It is very suitable for differential measurement, convenient for measurement, and easy to carry.