Brand Suckoo 4 Channel 6.35mm TRS or 3.5mm HiFi Audio Mixer Headphone Amplifier Splitter 1 Into 4 Out 1 Into 2 Out with DC Switch and Channel Switching, Mixer Controller. Suitable for cell phone computer MP3 musical instrument guitar player external 4 port audio headphones amplifier speakers and so on. This 2 in 1 audio headphone amplifier is very practical with 6.35mm TRS or 3.5mm HiFi audio jacks for connecting or controlling the volume level and amplification gain function of 4 headphones at the same time. Distribute one audio input signal to 4 external outputs, allowing 4 people to listen to the same source at the same time with individual control of volume level and gain. Input: 1 channel 6.35mm TRS or 3.5mm instruments, guitars, microphones, cell phones, computers, MP3 players. External: 4 channel 6.35mm or 3.5mm audio headphone amplifier speakers and other devices. Color: Black, Product Size: 10.3x5.6x3 cm: This product 1 set 5PCS 6.35 male to 3.5 female adapter 1 free DC adapter. This mixer can be externally connected to a 4 channel headphone mixing amplifier, which can individually control the volume level Gain, and can be switched to stereo or mono as needed to meet the needs of different users. This is useful for scenarios such as music production, recording studios, performances, or multiple viewings of movies. Overall, this Mixer Headphone Amplifier Splitter 1 Into 4 Out is a powerful, convenient and practical audio device that can help you to mix and distribute audio signals and adjust the volume level to amplify the gain.