Waterproof Referee Mobile Bluetooth Earphone Headset

Type    Stereo Bluetooth Headphone with Mic
Bluetooth Version    CSR 4.01 + EDR
Support Profiles    HSP, HFP, A2DP, AVRCP.
Operation Distance    10m
Transmitting Power    Class 2
Support TF Card    Up to 16G
Speaker Frequency Range    20~20KHz
Speaker Diameter (Driver Unit)    40mm
Impedance    32ohm
Microphone Dimension    4.5 * 2.2 cm
MIC Sensitivity    -54dB---2dB
MIC Impedance    2.2K
Battery    Rechargeable 3.7V / 160 mAh lithium battery
Talking Time    Up to 11 hours
Music Playing Time    Up to 10 hours
Standby Time    Up to 250 hours
Charge Time    About 2 hours
Charge Port    Micro USB
Plug Type    3.5mm
Audio cable length    1.0m / 3.0ft
Earmuff Diameter    7.5cm / 3.1in
Main item size (Foldable)    18.5 * 16.0 * 7.5cm / 7.28 * 6.29 * 2.95in