Amazon.com : Wasabi Power Battery for Panasonic DMW-BLF19 and Panasonic Lumix DMC-GH3, DMC-GH4, DC-GH5, DC-GH5S, DC-G9 : Digital Camera Batteries : Electronics
Vello BG-P1 Battery Grip for Panasonic Lumix GH3 and GH4 BG-P1
Amazon.com : Vello BG-P1 Battery Grip for Panasonic Lumix GH3 and GH4 : Electronics
Amazon.com : Wasabi Power Battery (2-Pack) and Charger for Panasonic DMW-BLF19 and Panasonic Lumix DMC-GH3, DMC-GH4 : Digital Camera Batteries : Electronics