A professional flash for the EOS-system, the 550EX offers every feature supported by the every EOS series camera in a package of exceptional workmanship. Full manual control of flash output is possible, or use the TTL flash capabilities of the camera it is mounted on. Combined with the optional ST-E2 Wireless Transmitter, multiple 550EX's can be combined to achieve a studio-like TTL effect.
Autozoom head covers from 24-105mm (17mm wideangle adapter included)
Compatible with every EOS camera, but has special features when used with E-TTL EOS cameras
Flash exposure compensation
Flash exposure lock
Second-curtain sync
Wireless TTL flash when combined with ST-E2 Transmitter & multiple 550 EX's
Stroboscopic mode shows several minute flashes continuously to easily view flash effect
4 Infared channels for multiple users in congested areas
Ratio flash lighting of up to 8:1 when used with ST-E2 Transmitter & multiple 550 EX's