Product Description: Material: metal + silicone Picture: Colors as shown in the picture Size: as shown in the picture Products include: 1x arc curve measuring instrument notes: (Size; 11.5*6.8*2cm) Please allow 1-2 cm error due to manual measurement, please confirm your idea before placing. Due to the different position of the picture, the color may have chromatic aberration. measurement, arc measurement, arbitrary curve measurement, irregular surface measurement, cylinder diameter measurement, accumulation/subtraction, measurement prompt sound, unit switching 99-meter ultra- measurement, single practical distance measurement of 0-99 , maximum 99-meter (automatic accumulation) ultra- measurement, millimeter-level accuracy, measurement data, automatic accumulation and subtraction, 10 groups of historical records can be called at any time, convenient practical. 15mm slim body, 30g light weight and 1/3 the size of a steel tape measure and 1/4 the weight, making it easy for you to carry around and measure at any time Lithium battery direct charging, 200 days long standby time application scenarios: flat surfaces, curved surfaces, irregular surfaces, circumferential diameters, and soft objects are all measurable, covering all of your life and work. Easy to use, convenient and efficient.