The built-in 3.7V/2000mAh battery charges fully in 2.5 hours and provides up to 14 hours of PTT operation, 12 hours of continuous music playback at maximum volume, and 90 hours of standby time. When connected to your radio via Bluetooth, simply press the PTT button on the microphone to communicate. This device is compatible with radios and mobile devices, including , Android phones, and tablets. When paired with a phone, it functions as a compact Bluetooth speaker for music playback or hands-free calling. The 2-pin microphone port works with radios equipped with a 2-pin headphone jack. It is not compatible with Kenwood, Pershing, Woolson, Baofeng, or Midland Radio models. Specifications: Material: PVC Bluetooth version: 4.2 Bluetooth protocols: HFP, HSP, A2DP, AVRCP, SPP Transmission range: Up to 10 meters Transmission power: Class 2, 4dBm Sensitivity: 80dBm with less than 0.1% bit error rate o decoding: SBC Signal-to-noise ratio: ≥75dB Speaker output: 1W/8Ω (116dB) Headphone jack: 3.5mm (supports PTT headsets) Battery capacity: 2000mAh/3.7V