The Ultrahuman Ring AIR Smart Ring in size 9 and Air Gold color is a unisex activity tracker designed for measuring heart rate. Made of titanium, it features wireless technology, Bluetooth compatibility, and a variety of sensors including SpO2, accelerometer, and optical bio-tracking. This ring is ideal for running and jogging activities, providing users with detailed information about their performance and health through features like distance traveled, exercise log, and sleep tracker. With its sleek design and advanced tracking capabilities, the Ultrahuman Ring AIR is a must-have for fitness enthusiasts looking to take their training to the next level. Retail: $349