Ultra-Long Endurance & Rapid Charging：Equipped with a high-capacity battery that provides over 140 hours of use per charge, plus Magnetic Fast Charging technology for full power in just 1 hour. Perfect for marathons, hiking, and long workouts without frequent recharging. Battery life may vary based on usage and settings.mentech Bluetooth Heart Rate Monitor High-Precision Tracking with Real-Time Alerts：Advanced optical sensor and dynamic algorithm deliver real-time heart rate updates every second. Customizable heart rate zones with vibration alerts help prevent overtraining. Not suitable for swimming Featherlight Comfort & All-Day Health Monitoring：Weighing just 19g, the aluminum alloy core and breathable elastic strap ensure all-day comfort. Tracks sleep cycles and SpO₂ levels overnight, generating insightful wellness reports to support your fitness goals Dual-Mode Connectivity & Reliable Offline Storage：Supports simultaneous ANT+ and Bluetooth 5.0 connections with smartwatches, gym equipment, and fitness apps. Built-in memory stores up to 1000 hours of data, ensuring your progress is always recorded—even without signal 5-Zone Training Display & Smart Coaching：The 5-color LED display instantly shows your current training zone (fat-burn, aerobic, anaerobic, etc.). The Mentech Sports App supports 10+ workout modes (cycling, running, etc.) and generates customized training plans for peak performance For the most accurate heart rate readings, wear the armband snugly against your skin (not loose) Passion Heart Rate Armband - 140+ Hours Ultra-Long Battery, ANT+/Bluetooth Dual Mode, High-Precision Dynamic Monitoring, 19g Lightweight Design, Multi-Sport Modes, Long