 "GoPro Dual - battery charger USB" " GoPro USB AHBBP301 Digital Camera Accessories CDWG.com
"Conveniently charge two GoPro Li-ion batteries simultaneously with the dual battery charger. Featuring USB compatibility, you can power it with most standard USB chargers, the GoPro wall or auto charger or a computer. Dual LED indicator lights display the charging status of both batteries: in process (amber) and fully charged (green)." 
 "GoPro Dual Battery Charger + (for HERO4 Black/HERO4 Silver) (GoPro Official Accessory)"@en-US "Camcorders - Page 2 | Come As You Arts"@en-US
"Compact Dual Battery Charger for HERO 4 batteries. Charge using any powered USB source (AC Adapter, Car Adapter, Laptop, etc.)."@en-US 