Feature: 1. PRODUCE PREMIUM SOUND: The analog preamp effect can produce a clean tone, making the guitar sound more concentrated, melodious, bright, and mellow. 2. DI DUAL BAND EQUALIZER: Treble Boost pedal switch increases the brightness of the tone, and the Anti Feedback knob is used to avoid volume feedback. 3. ADJUSTABLE VOICE FOCUS: The Anti Feedback knob can also control the degree of vocal concentration, turning left is the original sound, turning right will make the sound more powerful and clear. 4. ADJUSTABLE VOLUME: The volume can be adjusted through the INPUT knob, there is no sonic boom when amplifying the sound. 5. EXCELLENT MATERIAL: The aluminum alloy shell is lightweight and corrosion resistant, making the simulation effect pedal sturdy and durable. Specification: Item Type: Guitar Preamp Effect Power Supply: DC9V 100mA (without adapter), 6F22 9V battery (without battery) Control Knob: Input, feedback, bass, treble Pedal Switch: Anti feedback, treble boost Jacks: Input, output, balance out DC 9V Indicator: Input clip. Package List: 1 x Guitar Preamp Effect1 x Power Cord4 x Foot Pads