BTOSEP Smart Ring - IP68 Multiple Sports Modes Pedometer

Specification: Item type: smart ring. Material: stainless steel, EP. Battery type: lithium battery. Battery capacity: 20 mAh (included). Battery life: approx. 5 days. Charging time: approx. 30 minutes. Thickness: approx. 2.5 mm / 0.1 inches. APP: For intelligent health. Application: Thread fine thread into the needle for sewing clothes and measure the position of the carrying rings (finger attachment). Use a ruler to measure the length of the thread (pull the thread straight, align the points on both sides) and make sure to measure slightly firmly, otherwise it will be too large. The optical sensor sits close to the skin of the fingertip to ensure accurate data.