Features 1.APPLICABLE EQUIPMENT: Dual channel input and output, designed for having multiple sound sources and outputs, compatible with sound instruments, microphones, amplifiers, preamplifiers. 2.INPUT AND OUTPUT: The input is balanced circuit design, can be single ended input, can also be balanced input, single ended input with a large two pole mono plug, balanced input with a large three pole dual channel plug, long distance transmission can be balanced, close range can be, the output port is unbalanced single ended, using 6.5mm large two pole plug can be. 3.DUAL CHANNEL: Independent dual channel amplification, gain independent adjustment (0?20DB), the two channels can be used individually, can also be used at the same time, do not affect each other. 4.DURABLE DESIGN: Sturdy aluminum CNC chassis, beautiful and durable, working voltage between DC 5?12V, independent power switch, there is a simple LED light (5V power supply can be used with power bank or premium charging head, poor quality charging head will have AC sound). 5.EASY TO USE: With 6.35mm input and output jacks, this amplifier is easy to connect and operate. Simply plug in your devices and adjust the volume for instant amplification. specificationItem Type: Sound Amplifier Product Material: Aluminum Alloy Color: Black Power Supply: DC 5?12V Input and Output: 6.35mm (1/4 Inch) Gain: 0?20DB (Independent Adjustment) Operating Frequency: 20HZ to 20KHZ Input Impedance: Single Ended 10K, Balanced 20K Output Impedance: 200 Ohms Static Power Consumption: 0.3W Operating Current: 5V 73MA, 12V 30MA Size: Approx. 10.8x4.2x2.7cm / 4.3x1.7x1.1in PackageList 1 x Sound Amplifier 1 x USB Power Cable NoteAll data are measured manually, and there are certain errors in the measurement results.