・【Advanced Sleep Tracking】Precisely monitor your sleep patterns,heart rate,and blood oxygen levels with this smart ring design. ・【Durable Construction】Crafted from 314 stainless steel with IP68 water resistance,suitable for long-term use in various environments. ・【Long-lasting Battery Life】High-efficiency polymer lithium-ion battery offers 6-8 days of normal use or up to 15 days of standby time. ・【Comprehensive Health Monitoring】Easily track multiple exercise modes,heart rate,sleep quality,and blood oxygen levels. ・【Versatile Compatibility】Supports Android 5.1 and above,iOS 8.2 and above,with Bluetooth-compatible 5.3 connectivity for seamless integration. ・【Lightweight Comfort】Weighing only around 3.2g with a thickness of 2.6mm,it's comfortable for all-day wear. Specifications: ・CPU:AB2026B3 ・Storage:4Mb ROM+96 Kb RAM ・Heart Rate Sensor:HX3918 ・Battery Capacity:18mAh ・Charging Method:Charging Case ・Charging Time:Less than 60 minutes ・Battery Life:6-8 days (normal use),up to 15 days (standby) ・Water Resistance:IP68 ・Weight:Approximately 3.2g ・Thickness:2.6mm ・Operating Temperature:0-50℃ ・Bluetooth-compatible Version:5.3 ・Material:314 Stainless steel with Potting Process ・App Name:Da Rings ・Features:Activity tracking,Sleep monitoring,Exercise records,Heart rate monitoring,Blood oxygen saturation,Heart rate variability,Stress monitoring,Female menstrual cycle tracking ・Size: ・ 8 (18.2mm) ・ 9 (19.0mm) ・ 10 (19.9mm) ・ 11 (20.7mm) ・ 12 (21.5mm) ・ 13 (22.2mm) Package included: ・1xSmart Ring ・1xCharging Case ・1xEnglish Instruction Manual ・1xCharging Cable