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