Description [Mini HiFi Headphone Amplifier] Exquisite, compact, , portable, easy to carry [3.5mm AUX input and output] 3.5mm AUX input and output, signal-to-noise ratio 120dB and +N 0.0003%, not only output louder, more realistic stereo, no distortion. [Aluminum matte ] The stylish design provides you with a comfortable hand-held feeling, while the aluminum matte makes it . [Rechargeable lithium battery] Adopts rechargeable lithium battery with a capacity of 1500m AH, which can work continuously for more than 8 hours. [Wide and compact] It is significantly compatible with a variety of digital devices, such as MP3, MP 4, mobile phones and computers (Tip: It is not recommended to use it while charging, because current interference occur during charging, which may cause noise) Color:Black Material:Aluminum Alloy Package Contents: 1 * Headphone Amplifier Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.