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Visual Echoes FX3 Better Beamer Flash Extender for Use FX3 B&H
Flash Extenders – Tom Bol Photography, LLC
Amazon.com : Better Beamer Flash Extender FX-3 for Canon 580EX, 580 EX II, 600EX-RT, Metz 54-4, Nikon SB-700 : On Camera Shoe Mount Flashes : Electronics
Better Beamer FX-3 Flash Extender for Canon 580 EX II, Nikon SB-700 and more | eBay