Wireless Bluetooth Portable Speaker With TF Card Reader, FM Radio & Hands Free Calling 5W RMS stereo output with excellent bass and treble notes. Dynamic sound effects with crystal clear sound playback. This speaker has a 10m operating range and a rechargeable 300mAh battery for up to 2 hours of playback time at full volume For a true wireless stereo (TWS) effect you can now connect 2 x BT05 speakers to each other via Bluetooth and have a truly amazing stereo experience. Bluetooth version: 5.0 Charging time: Up to 2 hours. Playback time: Up to 2 hours for 100% volume level and up to 8 hours for 50% volume