Portable Emergency AA Battery Charger Extender suitable for the GoPro Hero4 / Hero 4 - with Gomadic Brand TipExchange Technology - Walmart.com
Amazon.com: Re-Fuel Dual Port Battery & Charger kit for GoPro Hero4 - GoPro Hero 4 Black/Silver Battery Charger : Electronics
Amazon.com : Smatree Battery (3 Pack) and 3-Channel Charger Compatible for Gopro Hero 4 (NOT for Hero 5) : Electronics
AHDBT-401 AHDBT401 Slim USB Battery Charger for Gopro Hero 4 Action Camera hero4 | eBay
GoPro HERO4 (AHDBT-401) Battery by Wasabi Power
GoPro Dual Battery Charger (for HERO4)
Amazon.com : PowerTrust 4-Pack AHDBT-401 AHDBT401 Battery for Gopro Hero 4 AHBBP-401 Digital Battery and AHDBT 401 Dual USB Charger for GoPro Hero4 HERO4 Camera : Electronics