Note: Please measure your finger circumference before purchasing, and then choose the appropriate size. APP software function: 1. step count, sleep, heart rate, exercise data recording, health monitoring, blood pressure measurement, blood oxygen measurement 2. Multiple exercise modes, photo taking Supported languages: Danish, Ukrainian, Russian, Croatian, Hungarian, Hindi, Indonesian, Turkish, Hebrew, Greek, German, Italian, Latvian, Czech, Slovak, Slovenian, Japanese, French, Polish, Thai, Estonian, Swedish, Lithuanian, Chinese (Simplified), Chinese (Traditional), Romanian, English, Dutch, Portuguese, Spanish, Vietnamese, Arabic, Chinese (Simplified), Chinese (Traditional), Chinese (Simplified), Chinese (Traditional), English (Simplified), Chinese (Simplified), Chinese (Traditional), Chinese (Simplified), Chinese (Simplified) English, Dutch, Portuguese, Spanish, Vietnamese, Arabic, Korean, Malay Product Specifications: Bracelet size diameter (mm): No.8: 18.1mm; No.9: 18.9mm;. No.10: 19.8mm; No.11: 20.6mm Color(Color): Black, Rose Gold Major function(Major function): "Steps, distance, calorie counting, heart rate, oxygen saturation, blood pressure, sleep tracking" Chip Manufacturer (Chipset Supplier): Lianrui Micro Chipset: RF03 APP: QRing Compatible System: Android 5.1 (including) or above, IOS 8.0 (including) or above. FLASH memory: ROM512KB Bluetooth: 5.0 low-power Bluetooth chip Battery Type: Li-Ion Polymer Capacity: 17mAh Charging Method: Magnetic Charging Waterproof Level: IP68 Charging time: about 1 hour Life-time: 5-7 days use, 15 days standby Appearance material: stainless steel Box size (L*W*H)MM: 75*75*43MM Product weight (Weight): 4.7g Package includes: 1x smart ring