Pilot USA Dual GA Headset Recording Adapter For GoPro Hero 3 / 3+ / 4 PA-80S/Hero3 | Pilotshop
Operating instructions GoPro Hero 4 - with book tip!
6 BEST Microphones for GoPro Hero 4 (Silver & Black)
QIUNIU External Microphone Mic + Transparent Skeleton Housing Case for GoPro Hero 4 3+ 3 Action Camera for Go Pro Accessories|Sports Camcorder Cases| - AliExpress