TF321 hot shoe adapter is suitable for all standard 518-2006 hot shoe flashlights, including 580EX 580EX II 550EX 430EX 430EX II Hot shoe adapter will be a good to your studio. Easy to use, very suitable for any of your photography needs. It have a PC synchronization socket, so you can connection additional studio lights or flashlights through the PC synchronization cable. This adapter can be used to connection flashing memory through standard hot shoes or PC synchronous line This hot shoe adapter is very suitable for installing Flashing memory without synchronization connector for connecting PC synchronization cable. It will allow these cameras to triggering external Flashing by using a sync line.