1.TF card mini speaker with recahrgeable battery 2.Small size, ... unique mini digital audio. 3. The new aluminum diaphragm micro-speaker, clear treble, bass, pure, unique design, the sound ... download, you can change the music anytime, anywhere. Speaker function parameters: output power RMS 3W THD=10% ... Frequency response 150-1800Hz(±3dB) SNR ≥80dB speaker unit 45mm product size 50*50mmWeight 80g