The BY-MP4 is a 2-channel audio adapter, with a 3.5mm TRRS cable and a 3.5mm TRS cable 
which allows you to shoot videos with Smartphone, DSLR camera or camcorder.
This adapter provides you with a compact dual-mic mounting and audio mixing solution, which allows
you to easily mount and control two microphones or wireless receivers. It requires no batteries or power source.
It has three Integrated Mounting Shoes to attach a variety microphones or wireless receivers, also others accessories, such as LED light, monitor etc.