Lightweight Ryze Element Smart Ring in Black, Size 9. At 2.5mm ultra-thin and weighing 6g, it delivers all-day comfort with a nano-ceramic outer and stainless steel inner construction. Tracks heart rate, blood oxygen, skin temperature, sleep, steps, distance, calories, menstrual cycle and provides recovery reports via the Ryze App while storing seven days of offline data. Smart touch controls manage music, camera and e-books, plus an SOS emergency call feature via your connected smartphone. Water resistant to 5 ATM, dust- and sweat-resistant. Ring battery life is 4–6 days typical (up to 20 days standby); the included charging case holds up to 180 days of charge, can recharge the ring up to 40 times, charges in under 2.5 hours and shows LED status indicators. Compatible with iOS and Android devices.