GoPro GoPro HERO4 Black Dual Battery, Charger, and Mount Kit
GoPro Hero4 Dual Battery Charger
GoPro Dual Battery Charger with Battery for HERO4 AHBBP-401 B&H
The Best GoPro Battery Charger for Hero4 Session - Outdoor Tech Blog
Amazon.com: Batmax 3 Packs 1680mAh AHDBT-401 Battery + LED Dual USB Charger with Type C Port for GoPro Hero 4 Black/Silver Action Cameras : Electronics