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Canon Speedlite 600EX-RT Flash 3pc Bundle Accessory Kit for Canon EOS 1D 1DS 1D X 5D Mark

New wireless multiple flash system using radio wave communication for enhanced control of up to five groups of flashes
Zoom flash head covers wide range of 20-200mm maximum Guide Number 197 ft60m at ISO 100
Redesigned contact construction improved flash head durability and exceptional dust and weather resistance for reliable operation
AF Assist Beam compatible with Canons new 61-Point High Density Reticular AF dot matrix LCD panel and backlit button provide easy visibility
18 Custom Functions for creative flexibility full swivel 180 degrees in either direction color filter holder for attaching Canon and third-party color gelatin filters