VAMOTRA Smart Ring for Women & Men, Fitness Tracker Ring with Heart Rate Monitor, HRV, Sleep Tracking, No Subscription Fee, 10ATM Waterproof Activity Ring for Android & iPhone (Matte Pink, 6) View on Amazon

VAMOTRA Smart Ring Fitness Tracker Ring for Women & Men, Sleep/Step/Blood Oxygen/Heart Rate Monitor, Long-Lasting Battery Sleep Ring, No Subscription Fee (Matte Pink, #9) View on Amazon