Features:

AMS Heart rate sensor--The highest precision sensor so far.Dual-Core Chip--The stability of monitoring heart rate while exercising.Continued brightness display with ULP--Clearly visible in the sunlight.An impossibly thin 8.4mm design--Thinnest in the world.30 Grams with all-metal appearance: 17-4PH Saintless Steel.Replaceable 20mm Wrist Strap (Medical Grade TPU Meterial) --Various designs of Wrist strap.The stability of Heart Rate monitoring up to 7 days--Accurately recording of dynamic and static Heart Rate.24 sports record management--Accurately records walking, running, push-up, rope skipping, badminton, table tennis, etc.Auto-Monitoring for sleeping up to 24 hours--Combined with heart rate curve to identify the sleep state.Battery life: Up to 7 days--Average 4 times power charging per month.Specifications: 

Type: BraceletBrand: iWOWNModel: i7Color: Black, Blue, Green (Optional)Wrist Strap: TPU    Bluetooth Portocol: BLE 4.0    Bluetooth Distance: 10m    Waterproofing Grade: 3atm/IP55    Battery Capacity: 3.7V / 100mAh      Voltage: DC 5VBattery Life: Up to 7days    Charging Time: about 1.5h    Data Storage: 7days    Charging time: about 90minDrop Test: 1.5 meters    Environmental Standard: -10° C~40° C    Bluetooth version: BT4.0Compatibility: iOS: for iPhone / 5 / 5S / 6 / 6S Plus / iPad or other above iOS 7.0; Android: Bluetooth 4.0 / Android 4.3 or aboveScreen size: Approx.39 * 31 * 8.4mm / 1.5 * 1.2 * 0.3in   Wrist strap Size: Approx.210 * 20 * 2.8mm / 8.3 * 0.8 * 0.1inProduct weight: Approx.41g / 1.4oz (include belt)Package size: Approx.28.5 * 6 * 3.5cm / 11.2 * 2.4 * 1.4nPackage weight: Approx.188g / 6.6ozNOTE:

1. May have Slight shade variation between the actual product and pictures due to illumination, photographic angle and configuration of monitor. We will try our best to send the product with the illustrated color as possible.2. You can download the APP "Zeroner health" from "APP store" or "google Play store", or scan QR code on the package.Package List:

1 * iWOWN i71 * Charger1 * User Manual (English)