Ray Flash Ringlflash Adapter for Nikon SB900 with D1, D2, D3, D700 DSLR Cameras Ray Flash: The Ring Flash Adapter Ring Flash for Canon and Nikon Portable Flash Units The unique Ray Flash is designed to replicate the lighting effect produced by heavy, tethered, powered studio ring flash units It's light, it's portable, and it requires no power other than your Nikon or Canon flash unit Uses Canon/Nikon hot shoe flash