Portable Bass Adjustable Headphone Amplifier 1. Core type: copper core 2. Number of branch connectors: single head 3. There is a volume control knob to adjust the volume 4. Portable and lightweight, smooth, sturdy case and chassis for long-lasting use 5. The sound quality is good, restores the real sound quality, reduces the distortion rate, and the sound quality is delicate and accurate 6. The use of 600mAH rechargeable lithium battery can keep the headphone amplifier working for more than 8 hours 7. Support most high-impedance 16-300Ω headphones, 3.5mm AUX input and output, signal-to-noise ratio>100Db, fully filter out noise 8. The signal of the input amplifier circuit is enhanced, not only can output a louder sound, but also output a clearer and more realistic stereo without distortion 9. Very compatible with various digital devices, such as MP3, MP4, iPhone, iPod, iPad, computer, CD player and personal media player, Xbox one, PS4, PS5 controller, etc. 10. Size: line length 0.5m, host length 10cm Packing list: -Host x 1 -Audio cable x 1 -Power cord x 1 -Instruction manual x 1