1、16 To 600Ω Impedance Headphones Supported: This headphone amplifier supports 16 to 600Ω impedance headphones, which helps high impedance or low sensitivity headphones to drive better, and can improve the volume and sound quality of headphones. 2、Multifunctional: This headphone sound amplifier features a two stage gain switch and bass boost function, which can both enhance the signal input to the amplifier circuit for optimal headphone performance, and work with the bass switch to provide a more detailed and mellow bass performance, giving you a more powerful music experience. 3、Easy To Use: This headphone sound amplifier is easy to use, you just need to connect the AMP to an sound source via a 3.5mm cable or Bluetooth, then connect it to your headphones and the music will stream to your headphones. 4、Multiple Connections: This headphone sound amplifier not only supports 3.5mm (AUX) voice input, but also Bluetooth connectivity, with SNR>100Db and THD+N 0.02%, it can output clearer and more realistic stereo sound without distortion. 5、Wide Application: This headphone voice amplifier can be used for such as MP3, MP4, cell phone, controller and Type C input compatible with for IOS laptops, more cell phones, computers, laptops. Item Type: HiFi Bass Headphone Sound Amplifier Material: Aluminum Alloy Input Port: 3.5mm(TRS) Charging Port: Type C(TRS) Charging Port: Type C Bluetooth Version: BT5.0 Built In Battery: 3.7V 1400mah Lithium Ion Battery (Built In) Charging Voltage: 5V, 500mA Backup Power: 38ma Maximum Operating Current: 250mA Duration: ≥6 hours 16Ω Headphone Power: 110mW 32Ω Headphone Power: 105mW 150Ω Headphone Power: 65mW 300Ω Headphone Power: 35mW 600Ω Headphone Power: 20mW Maximum Output VP P: 9.9VP P THD+N: 0.02% Signal To Noise Ratio: 100db Frequency Response 20HZ-20KHZ Phase Sound: 100db Sound Balance: 0.3db Operating Temperature: -20℃-60℃ 1 x HIFI Headphone Amplifier 1 x 3.5mm Sound Cable 1 x Charging Cable 1 x Manual