Features: Compact and light-weight design, easy to carry. Built-in distortion effect. Designed with 3 adjuster: Drive, tone, vol. 6.35mm/0.25in plug, just plug into guitar jack, no need of installation. Aux in jack lets you play along with cellphone or MP3 player. Comes with a splitter plug allow you to connect two headphones simultaneously. Powered by built-in rechargeable lithium battery. Specifications: Housing material: ABS+PC Power: Built-in rechargeable lithium battery Current: Max.20mA Product size: 8.7 * 8.1 * 2.9cm / 3.4 * 3.2 * 1.1in Product weight: 51g / 1.8oz Package size: 18 * 13 * 3.1cm / 7.1 * 5.1 * 1.2in Package weight: 116g / 4.1oz Package List: 1 * Guitar Plug Headphone Amp 1 * Cable 1 * USB Cable 1 * Splitter Plug