Features 1、[Extraordinary Sound Quality] The amplifier is equipped with high frequency electrolytic capacitors, has a noise reduction circuit design, and has no background noise, which can effectively gain audio and improve sound quality. 2、[Aluminum Alloy Shell] The aluminum alloy housing of the amplifier is very sturdy, has good anti interference and no loss of signal. 3、[Portable and Compact] The amplifier is small in size, easy to carry and use, and can enhance the sound quality of your device anytime, anywhere. 4、[Wide Compatibility] The amplifier is widely compatible with all audio equipment, and the input can be connected to DVD, CD, set top box, MP3, TV, game console or other equipment. The output can be connected to speakers, subwoofers, headphones, etc. 5、[Adjustable Volume] The amplifier has a volume adjustment knob, which can freely adjust the volume according to the user's needs. Specification Item Type: Mini Stereo Audio Preamplifier Material: ABS and aluminum alloy Input: RCA (L/R) , 3.5mm Output: RCA (L/R) , 3.5mm , phone Power Supply: DC 5V Battery: 1000 mah 503450 lithium battery (built in) Compatible Input Devices: DVD, CD, set top box, MP3, TV, cell phone, computer, tablet, turntable, sound card, guitar, bass, electronic musical instrument, game console or other device. Compatible Output Devices: Speakers, Subwoofers, Sound Blasters, Reverbs, AV Receivers, Post Amplifiers, Headphones, etc. Size: Approx. 87 x 50 x 37mm / 3.42 x 1.96 x 1.45in Package List 1 x Mini Stereo Audio Preamplifier 1 x USB Power Cable