Vello Battery Grip for Nikon Z6 II and Z7 II Mirrorless BG-N22
Amazon.com : FocusFoto Vertical Multi Power Battery Pack Grip Holder for Nikon Z6, Z7 Full Frame Mirrorless Camera Replace for MB-N10 EN-EL15 EL15B : Electronics
Remember this? Long-awaited Nikon Z6/7 battery pack to ship next month: Digital Photography Review