Auto zoom and bounce functions plus high-speed sync mode, FE Lock mode, AF Auxiliary Light and shoe lock. Zoom position is automatically set to any of six positions according to focal length data received for the lens when shutter button is partially depressed. In bounce flash position, zoom is automatically set at 50mm. Zoom positions are indicated by red LEDs on the back of the unit. Flash synchronization is normally set for first curtain.
Shoe mount for fully automatic operation.
Also may be connected via Canon off-camera TTL flash accessories. Green LED lights for 2 seconds to confirm automatic exposure after the flash is fired. At all other times Canon EOS cameras will emit beam. Will automatically turn on again with EOS cameras when the shutter button is depressed or when test firing button is depressed. Uses 4 AA-size alkaline, NiCd or lithium batteries.