8 to 10 Hours Battery Backup IP67 WATER PROOF & DUST PROOF Model: S20 （BT201） Material: Plastic Bluetooth Handsfree: Yes Bluetooth Version: V4.0 Operating Range: 10m Total Power: 3W X 2 Interface: 3.5mm /USB 2.0 Microphone: Yes SNR: ≥80DB Sensitivity: 80db Frequency range: 160Hz-20KHz Impedance: 4ohm Radio Tuner: Yes FM Frequency: 87MHz-108MHz Supports Card Type: TF Built-in Battery Capacity :3.7V/2000mA Battery Type: Li-ion battery Music Play Time: 5-8 Hours Plug Specifications: USB THD: ≤1% Charging voltage/current: 5V ± 0.25V / 0.5A Power Supply: 3.7V DC Color:black/green/blue/orange