Brand: AXON Model: F-188 Material: plastic Product Size: Approx. 43*19*9mm Color: beige Max sound output: 130dB±5dB Sound gain: ≥50dB Harmonic Wave Distortion: ≤5% Frequency response Range: 300Hz~4000Hz Input Noise: ≤ 30dB Power Voltage: 1.5 V Current: ≤ 4mA Battery Type: AG13