The Canon Speedlite 430EX flash unit replaces the Speedlite 420EX flash
model as the one of the most functional and powerful flashes in its class.
The maximum guide number has been increased to 43/141 (ISO 100, in
meters/feet), and the 430EX flash becomes even more versatile with the
addition of a built-in wide panel, which increases the minimum focal length
coverage from the previous 24mm limit to 14mm.