Product information:
Color: M1-BL10-Bluetooth light-Black
M1-BL10-Bluetooth light-navy blue
M1-BL10-Bluetooth light-medium gray
M1-BL10-Bluetooth light-Army Green
M1-BL10-Bluetooth light-pink
M1-BL10-Bluetooth light-light gray blue
M1-BL10-Bluetooth light-bright orange
M1-BL10-Bluetooth light-peacock blue
Transmission range: 10 meters
Chip type: Zhongke Lanxun
Battery life: more coal 8 hours
Material: Plastic
Usage: head up
Note:1. Asian sizes are 1 to 2 sizes smaller than European and American people. Choose the larger size if your size between two sizes. Please allow 2-3cm differences due to manual measurement. 2. Please check the size chart carefully before you buy the item, if you don't know how to choose size, please contact our customer service. 3.As you know, the different computers display colors differently, the color of the actual item may vary slightly from the following images. 
