Bluetooth phone calls Redmi Watch 4 connects to your smartphone via Bluetooth, allowing you to receive and reject calls on your watch and conduct conversations with an integrated microphone and speaker, all without having to remove your smartphone. Rotary stainless steel lace The exceptional stainless steel rotary lace adds high-end finesse even to the smallest detail, and its delicate rotation provides a more comfortable work. 20-day battery life Equipped with a large battery and energy-efficient system optimized for long operation. Enjoy 20 days of continuous battery operation in typical use mode! Comfortable, portable magnetic charging. 4-channel PPG sensor configuration Increased monitoring precision. The PPG sensor configuration has been updated to a 4-channel to increase the accuracy of health surveillance. A completely new structure for rapid dismantling The upgraded quick-release design facilitates the replacement of the bracelet. A number of bar options, change your style depending on your mood. Over 150 sports modes It supports a wide range of professional sports modes including outdoor and indoor running, walking, cycling and much more. Before exercising, you can warm up by following the moves of a professional trainer and get the right posture to reduce the number of injuries and strains. A huge 1.97 inch AMOLED display Explore the largest screen in Redmi Watch history, offering 26% larger display area. Combined with the 60Hz refresh rate, it provides an incredibly smooth and silky image. Smart sleep monitoring By using scientific, meticulous sleep monitoring technology, the watch records the quality of sleep in real time at various stages, from nap to REM phase. Improve habits and sleep quality. 24-hour heart rate monitoring Continuous and precise heart rate measurement provides constant protection. Breathing instructions will be sent when the stress level reaches 80 twice in a row during the vigil.