 "TomTom Runner 2 Cardio - Heart Rate Monitors & Sport Watches Blue"@en
 " Charge 2 Fitness Wristband (Large, Black) "Fitbit (Large FB407SBKL B&H"
 Display OLED Bluetooth Specification Bluetooth 4.0 Bluetooth Range 20.0' (6.1 m) Water Resistance Sweat, rain, and splash proof Memory Tracks 7 days of motion data Saves daily totals for past 30 days Stores heart rate data at 1 second intervals during exercise tracking and at 5 second intervals all other times Materials Wristband: flexible, durable elastomer material Clasp: surgical-grade stainless steel Battery Type Lithium-ion polymer (LiPo) Battery Life Up to 5 days Charge Time Up to 2 hours Sync Compatability Syncs with Mac OS X 10.6 and up, iPhone 4S and later, iPad 3rd generation and later, Android 4.3 and later, and Windows 10 devices Syncing requires Bluetooth LE and Internet connection. Windows 10 computers that do not have Bluetooth LE will need a wireless sync dongle in order to sync. Operating Temperature 14 to 113°F (-10 to 45°C) Maximum Operating Altitude 30,000' (9,144 m) Size Fits wrists 6.7 - 8.1" (17 - 20.6 cm) in circumference