RGBlink mini-mx Streaming Video Mixer or 35mm handlebar bolt

or 35mm handlebar bolt

High Pass Filter

Internal pop filter

Blackberry DTEK 50

Using it underwater with your GoPro will damage your camera and void the warranty

RGBlink mini-mx Streaming Video Mixer or 35mm handlebar boltMix and stream up to four HDMI video sources with the mini mx Streaming Video Mixer from RGBlink. The mini mx is a compact 4 channel streaming device that provides four HDMI 2. 0 inputs that support up to 4K60 resolution video. It also features dual mic inputs, internal mixing of embedded HDMI and external audio, and audio monitoring output for professional audio options. The switcher can be controlled and configured via a computer using RGBlink