Speedlite 420EX  Speedlite Flash Lineup Item Code: 4590A009
The new Speedlite 420EX is sure to appeal to EOS users
everywhere with its combination of power, features and
affordability. It's fully E-TTL compatible, and reverts to
standard TTL operation when used on older EOS bodies or the T90.
The fully swiveling bounce head zooms automatically over a range
of 24mm-105mm. Most impressively, its Wireless E-TTL
compatibility permits it to function as a "slave" unit,
triggered by a 550EX; ST-E2, or MR-14EX. Any number of 420EX and
550EX Speedlites can be combined as "slave" units.