Feature: 1. Mini preamplifier with impedance matching function for acoustic guitars. 2. Supports 2-band EQ(BASS \u0026 TREBLE) and volume adjusting. 3. 6.35mm plug for connecting musical instrument and 6.35mm output jack for connecting guitar amplifier. 4. It can also turn your home stereo into a guitar amplifier, allowing you to experience the pleasure of music performing. 5. ABS material and compact size, durable and lightweight, convenient to carry around. 6. Power Supply: 1 * 3V CR2032 battery(not included) Specification: Features: Mini preamplifier with impedance matching function for acoustic guitars. Supports 2-band EQ(BASS & TREBLE) and volume adjusting. 6.35mm plug for connecting musical instrument and 6.35mm output jack for connecting guitar amplifier. It can also turn your home stereo into a guitar amplifier, allowing you to experience the pleasure of music performing. ABS material and compact size, durable and lightweight, convenient to carry around. Specifications: Material: ABS Power Supply: 1 * 3V CR2032 battery(not included) Item Size: 9.5 * 4.5 * 2.5cm / 3.7 * 1.8 * 1in Item Weight: 33g / 1.2oz Package Size: 14 * 10.5 * 4cm / 5.5 * 4.1 * 1.6in Package Weight: 53g / 1.9oz Note: The guitar showed in the picture is not included. Package List: 1 * Preamplifier Package List: 1 * Preamplifier