Canon speedlite 430ez.
A specially designed, dedicated Speedlite for the original EOS-1. With Canon's sophisticated A-TTL flash shooting mode takes all the worry out of flash photography. Set your EOS-1 on program AE, choose the flash's A-TTL mode, and start shooting, with no worries about calculating shutter speeds, aperture values or guide numbers. The A-TTL flash output control system responds automatically to everything from shooting in very low light to daylight fill-in flash photography.
Guide number; 43 at iso 100
Head type; zoom, bounce and swivel.
Auto zoom function. Manual zoom function is also available.
Modes; Automatic A-TTL/TTL and variable manual power operation.
First and second curtain sync.
Power source; 4x AA batteries.
With case.