Circular Ring 2 (3.0g Single-Lead ECG & FDA AFib AI, $349) & Amazfit Helio Ring ($199 3.65g Titanium Palmar EDA Stress & Watch Fusion) Comparison
Electrophysiological-sensor, autonomic-stress, and subscription comparison of the $349 Circular Ring 2 (3.0g 2.55mm titanium smart ring featuring on-demand single-lead ECG recording, FDA-cleared Atrial Fibrillation detection, 8-day battery, 30-min wireless charging, and $0/mo Kira AI) and the $199 Amazfit Helio Ring (3.65g 2.6mm titanium ring with palmar Electrodermal Activity sweat-stress sensing, BioTracker PPG, 10ATM waterproofing, and $0/mo Zepp Watch+Ring data fusion).
⚡ Key Engineering & Supply-Chain Takeaways
- Circular Ring 2 ($349, 3.0g, 2.55×7.8mm PVD Titanium) embeds a dry-electrode single-lead Electrocardiogram (ECG) sensor and an FDA-cleared Atrial Fibrillation (AFib) rhythm classifier alongside 100Hz 3-wavelength PPG.
- Delivers up to 8 days of battery life in Power Mode (5 days in Performance Mode), recharges in 30 minutes on a wireless dock, and includes the Kira AI Health Strategist (140+ biomarkers) with $0/month subscription fees.
- Amazfit Helio Ring ($199, 3.65g, 2.6mm titanium alloy, 10ATM) integrates a palmar Electrodermal Activity (EDA) sweat-conductance sensor for sympathetic stress tracking and automatically fuses nocturnal ring recovery data with daytime Amazfit GPS smartwatch workouts in the Zepp App ($0/mo core fees).
🔬 Technical & Supply-Chain Specification Matrix
| Circular Ring 2 ($349) | 3.0g (2.55×7.8mm IP68/5ATM Titanium) / On-Demand Single-Lead ECG + FDA-Cleared AFib AI |
|---|---|
| Circular 2 Battery & Kira AI | Up to 8d Power / 5d Perf Battery (30m Wireless Dock) + $0/Mo Kira AI Strategist (140+ Stats) |
| Amazfit Helio Ring ($199) | 3.65g–3.82g (2.6×8.0mm 10ATM Titanium Alloy) / Palmar EDA Stress Sensor + BioTracker PPG |
| Helio Watch Fusion & Fee | Up to 4d Battery + Automatic Zepp Watch & Ring Readiness/VO2 Max Fusion ($0/Mo Core Fee) |
3.0g Single-Lead ECG & AFib Titanium Rings vs $199 3.65g Palmar EDA Stress & Athlete Recovery Rings
Official specifications from Circular and Amazfit highlight two bio-electrical smart ring architectures:
- Circular Ring 2 ($349, 3.0g): Combines on-demand single-lead ECG recording, FDA-cleared AFib detection, up to 8-day battery life, and $0/month Kira AI coaching.
- Amazfit Helio Ring ($199, 3.65g): Pairs a palmar Electrodermal Activity (EDA) sympathetic stress sensor and 10ATM titanium durability with automatic Zepp Watch + Ring athlete recovery fusion ($0/mo core fee).
🔗 Related AI Hardware in RECIWO Database
All 183 Devices →Circular Ring 2 3.0g Single-Lead ECG, FDA-Cleared AFib & Kira AI Titanium Smart Ring
3.0-gram titanium smart ring introducing on-demand single-lead Electrocardiogram (ECG) recording and FDA-cleared Atrial Fibrillation (AFib) detection on the finger, paired with 3-wavelength optical PPG, NTC skin temperature, 8-day battery life, wireless dock charging, and the subscription-free Kira AI health strategist.
Amazfit Helio Ring 3.65g Titanium Electrodermal (EDA) Stress & Athlete Recovery AI Ring
3.65-gram, 2.6mm titanium-alloy smart ring engineered for athletic recovery and autonomic nervous system tracking, combining a palmar Electrodermal Activity (EDA) sweat-conductance emotion/stress sensor, BioTracker™ dual-color PPG, skin temperature, 10ATM waterproofing, and seamless Zepp App watch-plus-ring data fusion at $199.
Oura Ring 4 3.3g All-Titanium 18-Path Smart Sensing & AI Advisor Biometric Ring
3.3-gram all-titanium smart ring featuring a fully recessed, bump-free titanium interior and Oura's 18-path multi-wavelength Smart Sensing optical platform—dynamically adapting to finger rotation to boost SpO2 signal fidelity by 120%, cut nocturnal heart-rate gaps by 31%, and power the conversational Oura Advisor LLM.
Samsung Galaxy Ring 2.3g Concave Grade-5 Titanium & Galaxy AI Gesture Smart Ring
2.3-gram concave Grade-5 titanium smart ring engineered for the Samsung Galaxy AI ecosystem, integrating optical PPG, skin temperature, and 3-axis motion sensors with Double-Pinch finger gesture controls, a 361mAh transparent LED clamshell charging case, 7-day battery life, and $0/month subscription fees.
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A technical electrophysiological-sensor, autonomic-stress, and subscription-model comparison of the Circular Ring 2 ($349, 3.0g 2.55mm titanium smart ring featuring on-demand single-lead ECG recording, FDA-cleared Atrial Fibrillation detection, 8-day battery, 30-min wireless charging, and $0/mo Kira AI), Amazfit Helio Ring ($199, 3.65g 2.6mm titanium ring with palmar Electrodermal Activity sweat-stress sensing, BioTracker PPG, 10ATM waterproofing, and $0/mo Zepp Watch+Ring data fusion), and Oura Ring 4 ($349).
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