Feature: 1. Includes 10X preamp tone board as well as treble, mediant, bass and volume control. 2. Selection premium electronic components, adopt NE5532 operational amplifier, high quality potentiometer, for black BP Promise coupling capacitor, 1% metal film resistor, capacitors, etc. 3. With op amp IC socket, convenient to upgrade for flexible use. 4. Reasonable circuit board layout, small noise, beautiful component layout. 5. AC 12V-18V dual power supply voltage. Specification: Item Type: NE5532 Preamplifier Tone Board Supply Voltage: Dual Power Supply AC 12V-18V Number of Channel: Dual Channel Adjustment Type: 4 channels (Treble, Mediant, Bass, Volume) Audio Input:For RCA socket Audio Output: 3P terminal Input Voltage: 3P terminal PCB Size: 112x68x23mm / 4.41x2.68x0.91in Installation Size: 98.5x47.5mm / 3.88x1.87in Mounting Hole: 3mm/0.12in Note: Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering. .w-e-text table td,.w-e-text table th,;.w-e-text table, Package List: 1 x NE5532 Preamplifier Tone Board 4 x Gasket 4 x Knob 4 x Nut Includes 10X preamp tone board as well as treble, mediant, bass and volume control. Selection premium electronic components, adopt NE5532 operational amplifier, high quality potentiometer, for black BP Promise coupling capacitor, 1% metal film resistor, capacitors, etc. With op amp IC socket, convenient to upgrade for flexible use. Reasonable circuit board layout, small noise, beautiful component layout. AC 12V-18V dual power supply voltage.