The Flash X-Tender (Better Beamer) FX-4 Flash Output Booster for the Nikon SB-600 and SB-800 Flashes with Lenses 300mm
Now 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 birds and animals to life with an eye highlight. Used and praised by nature photographers world-wide. When used with TTL (Through-The-Lens) flash metering, exposure is automatically handled by your camera and flash, and no special compensation is required.