Product Description Features: Compact and lightweight design, no larger than an adult's hand. Built-in distortion effect for enhanced sound quality. Equipped with three adjusters: Volume, Tone, and Gain. Convenient clip on the back for easy attachment to a belt, pocket, or other locations. Powered by two AAA 1.5V batteries (not included). Specifications: Instrument jack: 6.35mm mono socket Max. input level: -10dB Input impedance: 1M Ohm Headphone jack: 3.5mm Link jack: 3.5mm 4-pin socket Link input impedance: 100K Link output impedance: 10K Power: Two 1.5V AAA batteries Product size: 9.8 x 4.7 x 3.5 cm / 3.9 x 1.8 x 1.4 in Product weight: 56g / 2oz Package size: 12.6 x 7.6 x 3.8 cm / 5 x 3 x 1.5 in Package weight: 91g / 3.2oz Package List: 1 x Headphone Amplifier 1 x Connecting Cable 1 x Converting Cable 1 x User Manual (English & Chinese)