The new Nikon MB-D17 Multi Power Battery Pack for D500 is now on sale at Amazon US for $352.80, but “Temporarily out of stock”. The B&H price of Nikon MB-D17 battery grip is $399.95. So you can save $47.
Nikon MB-D17 Battery Pack for D500: $352.80 at Amazon.
Product Description from Amazon:
The Nikon MB-D17 is a Multi-Power Battery Pack for the Nikon D500 DSLR camera that increases the number of shots per charge that you can get. It features a shutter release button and Fn button for ease in vertical shooting. The MB-D17 can be powered by 8 AA batteries or by a single EN-EL15 or EN-EL18a lithium-ion battery (all sold separately).