PULSE RATE RANGE：30 to 250 bpm. WIRELESS：Bluetooth 4.0 BLE. COMPATIBLE WITH：iOS 9.0 or above, iPhone 4s/iPad 3 or above; Android 5.0 or above, with Bluetooth 4.0 BLE. 【Designed for Kids】Patented soft O2 ring sensor designed specifically for 3-10 year-old children is more convenient and won't fall off.
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