Better Beamer Flash Extender FX-3 for Canon 580EX, 580 EX II, 600EX-RT, Metz 54-4, Nikon SB-700Now there is an easy way to have the extra "flash power" you need in the field. The Flash X-Tender packs flat, weighs less than 3 ounces and sets up in 30 seconds and your flash output is extended a minimum of 2 full f-stops! Bring your birdsand animals ..