B08FRSB1CM Media Mod (HERO9 Black) – Official GoPro Accessory (ADFMD-001)

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Built-in directional mic highlights voice audio and reduces ambient noise
Tough, weather-resistant construction withstands the elements
2 cold-shoe mounts to attach your favorite lights, mics or LCD screens
3.5mm mic port lets you add an external mic for enhanced audio
HDMI-out port to monitor or play back your footage