MicW iGoMic Professional External Microphone for GoPro Hero 2, 3 and 3+ Camera | Drone and Action Camera Specialists
Amazon.com: SOONSUN Frame Mount Housing Case with External Lavalier Lapel Clip-on Microphone for GoPro Hero 3, Hero3+, Hero 4 Black White Silver Action Cameras : Electronics
3.5mm External Microphone Clip On Mic + Adapter Cable Kit for GoPro Hero 4 3+ 3 | eBay
Amazon.com : GEPULY Skeleton Housing Case for GoPro Hero 4, Hero 3+, Hero 3 Action Camera Side Open Protective Housing Case with Skeleton Backdoor and LCD Touch Backdoor for GoPro Hero4, Hero3+,
GoPro 3.5mm Mic Adapter for HERO3 / HERO3+ / HERO4 - Filters Exchange Photography Accessories