Vello BG-N12 Battery Grip for Nikon D3100, D3200, & D3300
Amazon.com : Neewer Professional Vertical Battery Grip Replacement for Nikon D3100/D3200/D3300/D5300 SLR Digital Camera, Works with 1 or 2 Pieces EN-EL14 Batteries : Electronics
Nikon D3500 DSLR | Interchangeable Lens Camera
NEEWER Vertical Battery Grip for Nikon - NEEWER – neewer.com
A Less Expensive Battery Grip for the Nikon D810 & D800: Vello BG-N7 Review