Highly sealed. IP67 real waterproof, could support wear when swimming, from apltch only(dear people, we suggest that you fully dry it after taking it out of water for charging protection and frequently using it or long time in water may influence its working life which is out of our warranty, thanks for your understanding) Heart rate monitor uses the brand new dynamic algorithm to monitor the heart rate which is more accurate and more reliable than other smart bands as most of other smart bands in the market are only with static algorithms. Smart band model: Mantara is the only actual vendor for this listing, any other vendor giving on this listing is giving false items which will be involved in the brand infringement and we will take actions for this. And nbsp, you could tap the new to see the chart from us if you didn't find our chart hardware specification: Display: 1.3 OLED screen 240*240 LED Display operation: Curved monitor sensor : BST-BMA253 and Data Save Time 3 months acceleration bluetooth: Compatible bluetooth 4. 0 (android and ios)ble contact type: Contact charging battery: 200mah polymer battery standby time: 5-6 Days compatibility: Android 4. 4 or above, ios 8. 0 and above watch strap material: Silicon Gel weight : 46 gram waterproof level: IP67 waterproof functions: Incoming call reminder, sms reminder, app notifications reminder, alarm clock, sleep detection,health and fitness tracker, step count, simulation Yes heart rate monitor: Yes fatigue value monitoring: Yes pedometer, step calorie tracker, sedentary reminder: Yes others tools: Alarm clock, bluetooth-camera language: English.