Jobu SF-BP2 Surefoot - Bodyplate 2

A square format body plate for affixing to most Pro size SLR cameras, or cameras with an accessory battery pack.
The curve on the back of the camera is 1/2", roughly the same as Canadian or US dime.

Nikon Fit:
Nikon D1, D2H, D2X, D3, D3x series
Battery packs: MB-D10/D80/D200/D100, MB-40

Canon Fit:
EOS 1D/1Ds series
Battery Pack Fit: BG-E1/E3/E4/E5, etc.