Expoimaging RAC170 Ray Flash Ring Flash Adapter for Canon 580EX & Canon 5D, 40D, 30D, 20D, 10D Minimal light loss from the flash's standard output Does not affect flash's color temperature Requires no modifications to flash unit For Canon 580EX Used with 5D, 5D Mark II, 10D, 20D, 30D, & 40D, Olympus FL-50R with E-3, E-410, E-420, E-500, & E-510, and Sony HVL-56AM with A100, A200, A350, & A700