Pixel TF-321 flash hot shoe adapter enables you to trigger flash attached on top of the adatper hot shoe as well as other flash connected via PC sync lead. It fits all Standard ISO 518-2006 hot shoe flashgun including 580EX, 580EX II, 550EX, 430EX, 430EX II etc. It has a PC sync socket so you can connect an additional studio light or flash via a PC sync cable.