Feature: 1. Microphone Mixer: The mixer supports 4 condenser microphones working at the same time, with independent volume, and the total mixing output is connected to the mic input of the sound card or computer. 2. Good Audio Mixing: The condenser microphone mixer can be magnified by 4 times to perfectly listen to music and mix multiple audio sources, including smartphones, tablets, computers, MP3 players, etc. 3. Enjoy Your Music: The small microphone mixer extender is convenient to carry and operate, and can mix multiple audio sources infinitely. New rail to rail operational amplifier brings beautiful and dynamic sound. 4. 3.5mm Interfaces: The 3.5mm interface of the microphone mixing expansion board own bias voltage, which is plug and play. It can be connected to common electric microphones, condenser microphones, etc. 5. 4 In and 1 Out: This 4 in 1 out microphone mixer can be connected to 4 audio source inputs at the same time. Each audio track has an independent volume adjustment knob, which can be output through headphones and speakers. Specification: Item Type: Condenser Mic Mixer Model: MC-401 Material: Aluminum Alloy Voltage: DC 5V Sound Input Interface: 3.5mm/0.1in (approx.) Sound Output Interface: 3.5mm/0.1in (approx.). Package List: 1 x Condenser Mic Mixer1 x USB Power Cable Note: If the USB to DC power cord makes noise, please use the 5V power adapter.