Accent your style while enhancing your fitness with the viivosmart 4 activity tracker. This slim, smart wristband is loaded with features to track your daily activity and your sleep stages all night. Wrist-based heart rate and Pulse Ox sensors help you learn more about your body, with all-day stress tracking, Body BatteryTM energy monitoring, VO2 max and more. Smart notifications keep you connected, and up to 7 days of battery life keep you going strong. KEY FEATURES: STYLISH DESIGN: Slim, smart activity tracker blends fashionable design with stylish metal accents and bright, easy-to-read display. ADVANCED SLEEP MONITORING: Includes advanced sleep monitoring with REM sleep stages and a Pulse Ox3 sensor at the wrist to gauge blood oxygen saturation levels (Accessing the Pulse Ox feature regularly will affect battery life). BODY BATTERYTM: Uses heart rate variability (HRV) to determine your bodyâs energy level â higher number suggests youâre ready to go; lower number suggests you may need rest. ALL-DAY STRESS MONITORING: All-day stress monitoring enables users to see periods of elevated stress or restful recovery. Includes easy-to-follow relaxation breathing exercise. WRIST BASED HEART RATE: WHRM gives you heart rate monitoring all day and night â no additional strap required. VO2 MAX: is an excellent way to measure your aerobic fitness and should increase as your fitness improves. SMART NOTIFICATIONS: Get vibration alerts for all notifications including calls, text messages and more (pre-set text responses for AndroidTM users) when paired with a compatible device. CONNECTED FEATURES:Automatic syncing to Garmin Connect, TrueUpTM multitracker synchronization, music controls, HR broadcast, find my phone, find my device and VIRB camera control when paired with a compatible device. 24/7 WEARABILITY Swim rated and can be worn in the shower or pool; up to 7 days of battery life. ACTIVITY TRACKING: Steps, floors climbed, calories burned, intensity minutes, Move IQ and more. MOVE IQ: Automatically starts activity timer, detects familiar exercise types and displays events in Garmin Connect.