Rode VXLR+ 3.5mm TRS Female to XLR Male Adapter w/ Phantom Power Converter You can even mount two

You can even mount two GoPro's on the arm

Eleven Lite

This triple charger is made for GoPro Hero5/6/7 Black batteries

because in order to use an external mic you also need the pro audio adapter (sold separately) which would always be hanging free and banging on the side of the camera

The Rycote Stickies are double sided adhesive pads used for mounting lavalier microphones to clothing and skin

Rode VXLR+ 3.5mm TRS Female to XLR Male Adapter w/ Phantom Power Converter You can even mount twohe Rode VXLR+ is an adapter that lets you connect a mic equipped with a 3. 5mm TRS connector to the XLR input of a professional camera, recorder, or mixer. The VXLR+ also converts 12 to 48V phantom power down to 3 to 5V plug in power, allowing lavalier, headset, and shotgun mics to receive power from the XLR connector. Compact and lightweight, the adapter is terminated by a 3. 5mm female TRS connector at one end and an XLR male connector at the other.