Feature: 1. Wide Compatibility: This headphone amplifier supports a wide range of high impedance headphones. With 3.5mm AUX input and output, it ensures clear audio quality and reduces noise, allowing you to enjoy enhanced sound performance. 2. Two-Stage Gain Switch: This headphone amplifier enhances the signal from the input to the amplifier circuit, enabling optimal headphone performance. It delivers louder output with clearer, more detailed stereo sound and minimal distortion. 3. Rechargeable Lithium Battery: Equipped with a built-in 1500mAh rechargeable lithium polymer battery, this amplifier provides over 8 hours of continuous use. It includes a volume control knob for easy adjustment. 4. Portable and Lightweight Design: Compact and lightweight, this amplifier is ideal for on-the-go use. The durable aluminum alloy casing offers reliable protection for long-term durability. 5. Broad Device Compatibility: Compatible with various digital audio devices such as MP3 players, MP4 players, smartphones, computers, CD players, and personal media players, making it suitable for multiple audio setups. Specification: Item Type: Audio Amplifier Material: ABS Built-in Lithium Polymer Battery: 1500 mAh SNR: 120 dB Output Power: 2000 mW, 16 Ohms Package List: 1 x Audio Amplifier 1 x USB Cable 1 x Audio Cable 1 x User Manual