Specifications Hign-concerned Chemical:None Waterproof Grade:5ATM Model Number:R9 Display screen:No NFC Support:No Activity Tracked:Activity Tracker,Steps Tracker,Distance Tracker,Calorie Tracker Metrics measured:Heart Rate Monitor,Sleep Monitor,Blood Oxygen Monitor Item Weight:5.5g Case Material:STEEL Certification:ce,FCC Battery Capacity(mAh):18mAh Color:Black,Silver App:ECTRI Material:Stainless Steel Type:Smart Ring For Men Women Product Parameters: CPU:Pixart 2860 Material: Stainless Steel. Bluetooth Version:5.1. Battery capacity:18mAh. Usage time:3-5 days Charing time:0.5H. G Sensor:QMA6100P. Heart Rate Sensor:HX3605. Magnet Cable(With SMT Protect IC). Waterproof Level:5ATM Waterproof Charging Requirement:Charging 1A or less. APP:ECTRI system requirements:"Android: 6.0 or above./iOS: 11.0 or higher. Main Function: Heart rate detection Blood oxygen test blood pressure detection Remote photography Multiple sport modes Gesture controlTiktok photograph e-book music Somatosensory games Sleep detection (Sleep time ,Sleep quality) Step count Synchronous data to APK/APP Note: Please take off the ring and wash it after bathing to avoid skin damge caused by residual toiletries inside the ring.