Features 1、Helps to deliver high-quality guitar sounds, retaining the sound output of the guitar. 2、AUX jack lets you connect an external audio device to this jack. 3、Uses the headphone jack to connect headphone, portable speaker or mixer. Specification The headphone amp is compact and light-weight design, not bigger than a hand of the adults, easy to use and carry. Features: Helps to deliver high-quality guitar sounds, retaining the sound output of the guitar. Designed with 3 knobs: blend / tone / volume knob. AUX jack lets you connect an external audio device to this jack. Uses the headphone jack to connect headphone, portable speaker or mixer. Powered by the built-in battery. Comes with a USB cable for charging the item. Compact and light-weight design, not bigger than a hand of the adults. Specifications: Power Supply: Built-in 180mAh 3.7V rechargeable battery Working Current: 37mA Item Size: Approx.8 * 8 * 1.2cm / 3.1 * 3.1 * 0.5in Item Weight: Approx.33g / 1.2oz Package Size: Approx.14 * 11 * 2cm / 5.5 * 4.3 * 0.8in Package Weight Approx.70g / 2.5oz Note: The headphone is not included. Package List: 1 * Headphone Amp 1 * USB Cable Package List 1 * Headphone Amp 1 * USB Cable