Specifications: Bluetooth Name：B39 Bluetooth Version: V5.0 Battery capacity：350mAh lithium battery Charging Time: About 2.5 hours Talk Time: up to 8 hours Standby Time: up to 20 Days Support Bluetooth Mode: A2DP 1.2, AVRCP 1.0, HSP, HSF 1.5 Frequency: 2.402-2.480GHZ, 2.4G ISM band RF Performance: receiver sensitivity: -84dBm; transmit power up to 4dBm Frequency Response: 20 Hz - 20 KHz Signal to Noise Ratio (SNR): 70Db; Total Harmonic Distortion Rate (THD) 0.1% Power Indicator: Red and blue lights alternately flashing.
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