Features 1.PROVIDES MAXIMUM FLEXIBILITY: Mini Headphone Amplifier is designed for use with all types of headphones, offering maximum flexibility. 2.ULTRA LOW NOISE: 4 channel stereo headphone amplifier operates with the ultra low noise 4580 to ensure excellent sound performance. 3.INDEPENDENT OUTPUT LEVEL: Headphone amp amplifier utilizes 4 channels to set independent output levels for a wide range of listening needs. 4.INDEPENDENT VOLUME CONTROL: Headphone amplifier achieves maximum sound quality even at maximum volume. Volume of each output channel can be controlled independently. 5.RANGE OF APPLICATION: 4 way headphone amplifier is an ultra compact stereo headphone amplifier for studio and stage applications. specificationItem Type: Headphone Amplifier_x000D_ Material: Iron Shell_x000D_ Input:_x000D_ Type: 1/4 Inch TS Connector, Stereo_x000D_ Impedance: 100k_x000D_ Maximum Input Level: +15dBu_x000D_ Headphone Output:_x000D_ Type: 1/4 Inch TS Connector, Stereo_x000D_ Impedance: 80k_x000D_ Maximum Input Level: 40mW In 100_x000D_ Voltage: 100-240V PackageList1 x_x000D_ _x000D_ HeadphoneAmplifier 1 x Instruction Manual 1 x Adapter