W8 Round Shape Heart Rate Tracker Sport Multi-functions Smart Watch – Black

• Thin and light, finely crafted extraordinary quality smart watch 

• Recording steps, calculate and show in the APP walking distance, calories burnt 

• 2.5D tempered glass, 1.3 inch screen, display with more data 

• Health monitoring, intelligent light senor real-time blood pressure, blood oxygen, heart rate measurement

• Incoming text notification, phone calls, text message, App notification reminders

• IP67 rated water resistance, vibration reminder

• Real-time weather update

• Note: 

• The bracelet can't touch the hot water because the hot water has water vapor. 

• For the problem that the bracelet can measure the heart rate in things and in the air, the following explanation is made: 

• At present, the mainstream heart rate bracelets on the market adopt the same measurement method. 

• The principle is not complicated, that is, the PMG signal of the radial artery is obtained by the reflective photoelectric measurement method, and the fast Fourier transform is performed on the PPG signal to analyze the frequency domain. 

• To achieve the detection of the human heart rate. 

• To put it simply, it is to use a light to the artery and then reflect it back. 

• Based on the change of the reflected light, the heart rate of the human body is calculated. 

• Due to many factors such as the physiological structure of the human body, the color of muscles and blood, green light is the color with the highest passing rate in the human body. 

• Therefore, the light source of the heart rate sensor uses green light to achieve minimum loss and interference. 

• Heart rate wristband detection focuses on human tissue. Some data is also read for non-human objects. 

• This is a known and normal phenomenon. After the data is based on the principle of light reflection, the heart rate detection will have a reading. 

• This situation cannot be All avoided, so there will be problems with heart rate data in the case of heart rate bracelet (table) in the case of "air test".

Specification: 

• Wristband Size(mm):about 255mm*20mm*2.3mm 

• Product Net Weight (g): about 45g 

• Main Display : 1.3 " TFT 240*240 

• Type of battery: li-ion battery 

• Battery Capacity: 170mAh 

• Standby time: about 5-7 days 

• Normal use time : about 3-5 days 

• Charging Time: About 2hours 

• Alert type: Vibration