Brand New Oura Ring Gen 4 in silver, size 9; opened; never set up or used ACCURACY - SMART SENSING - Oura tracks over 50 health metrics, including sleep, activity, stress, heart health, and women’s health metrics. Oura Ring 4 is powered by Smart Sensing, which adapts to you — delivering accurate, continuous data, day and night LONG LASTING BATTERY - With up to 8 days of battery life, no screens and no vibrations, Oura Ring 4 allows you to focus on the present. From a workout to a night out — you’re free to forget it’s on. Until you start getting compliments Additional Features Activity Tracker, Cycle Tracking, Daily Workout Memory, Lightweight GPS Geotagging Functionality GPS Via Smartphone Band Material Type Stainless Steel Case Material Type Titanium Water Resistance Level Water Resistant Human Interface Input Buttons Supported Application Fitness Tracker Water Resistance Depth 100 Meters Supported Satellite Navigation System GPS Controller Type Ring Metrics Measured Body Temperature, Menstrual Cycle, Sleep Duration, Stress Closure Type Slip On