" http://www.amazon.com/gp/product/B001BTG3OQ?tag=httpblogtrave-20
High-quality flash for standalone use or as part of a comprehensive lighting system
Commander mode controls up to 3 Speedlight groups or unlimited individual Speedlights
4 wireless channel options prominent master and remote control switch for wireless operation
Auto power zoom coverage ranges from 17 to 200mm FX format to 12 to 200mm DX format
3 light distribution patterns measures 3 x 57 x 47 inches W x H x D and weighs 146 ounces
Nikon SB-900 AF Speedlight Flash for Nikon Digital SLR Cameras"