Feature: 1. Sleep Monitoring: The smart ring health tracker grades the sleep based on the proportion of rapid eye movement sleep, light sleep and deep sleep throughout the sleep cycle and gives recommendations accordingly. Get a clearer understanding of the factors affecting your health and athletic ability. 2. Water Resistance: With a 50m water proof rating, the smart health ring provides reliable water resistance during water related activities such as swimming and showering. The water proof and sweat proof design makes it a smart health assistant in your life. 3. Health Monitoring: The fitness ring accurately records running distance, calories burned and activity time, keeping you informed of your progress throughout the day. Support walking, running, cycling and other regular exercise and map trace exercise, you can view the data in APP after exercise, including exercise time, distance and calorie consumption. 4. Comfortable to Wear: The smart ring is rugged, lightweight and comfortable to wear, ensuring stable performance for a prolonged period of time. Designed to be lightweight and comfortable, it takes up very little space on your hand and is suitable for wearing all day without discomfort. 5. Lasting Battery Life: The ring is powered by an extra low power control chip and a 20mAh capacity lithium battery, which significantly improves the ring endurance performance through indepth power management and low power mode selection. The battery lasts 7‑10 days under normal use conditions. Specification: Item Type: Smart Ring Material: Stainless steel Battery Type: Lithium ion Battery Capacity: 20mAh (built in) Water Proof Level: 50m Application Support: for Android 6.0 and above, for IOS 11.0 and above, support BT5.1 Ring Thickness: Approx. 3mm / 0.12in Charging Method: Magnetic charging. Package List: 1 x Smart Ring 1 x USB Cable 1 x User Manual