Good evening, my name is Darryl Madison. I have a Canon speedlite 420 external flash. My infrared cover came off and the two lights that were protected are now exposed. Do you carry the part? I believe the part number is CY2-1130

SOURCE: canon speedlite 540ez

I am having the exact same problem, but i just realized that this flash probably is not compatible with my newer canon digital rebel XT... are you using it with this camera or is this the same setup you've used before with success?

SOURCE: Speedlite 420EX lost a plastic part

Part number: CY2-1130-000 PANEL, AF LED 
Check you local canon.com for spar part suppliers

SOURCE: Can the Canon speedlite 430EX be the slave to the 550EX speedlite

Most any slave light will work I use a old vivitar flash with a slave module in the cord to camera outlet woks gook for a fill light. helix camera .com ritz camera. or ebay don't digital flashes a little different than strobes i played with the settings until i got the desired lightng I wanted., if your camera has a hot shoe you can get a slave to fire an external flash with it.hope i helped

SOURCE: camera does not fire external flash

Also be certain that the flash is screwed onto the shoe as tightly as possible.

SOURCE: canon speedlite 430 EZ does not match with canon

You can't. The metering systems are incompatable. You must use the EX range with the 400D, such as 430EX or 580EX (versions I or II)