Oura Ring 4 in Black (Size 13) w/ original Charging Dock and USB-C Cable.

Oura Ring 4 in Black (Size 13) w/ original Charging Dock and USB-C Cable.  This was only used for a couple of months, since my boyfriend just couldn't get used to wearing a ring. Works perfectly!  Comes complete with its official silver charging dock and USB-C cable. Fully tested, cleaned, and ready to pair with a new Oura account.  Model: Oura Ring 4 Color: Black Size: 13  Condition: Great pre-owned condition with light cosmetic wear from normal daily use (see photos).  Includes: Oura Ring 4 (Size 13), Size 13 Charging Dock, USB-C Cable.  Key Features: *Smart Sensing Technology: Upgraded algorithm and sensor recessed design that adapts to your finger for continuous, more accurate data collection.  *All-Day & Night Health Tracking: Monitors 24/7 heart rate, Heart Rate Variability (HRV), daily Readiness scores, and daytime stress levels.  *Advanced Sleep Analysis: Tracks sleep stages (Deep, Light, REM), restful sleep quality, and blood oxygen (SpO2) sensing.  *Full Titanium Design: Sleek, fully recessed interior sensors for increased comfort compared to older generations.  *Activity & Fitness Tracking: Automatically detects workouts and daily movement, syncing seamlessly with Apple Health, Google Health Connect, and Strava.  *Extended Battery Life: Up to 8 days of battery life on a single charge.  *Water Resistant: Rated water-resistant up to 100 meters (328 ft).