This is the sync cord, used with the hotshoe connect shown and the little plug pin on the left. The plug pin goes to the strobe or to the flash meter, depending on which you are using at the time. Hope this helps ease some of the mystery! Frankly, when I went to get a strobe I was lost as a fish in muddy water...opened the box and felt bewildered then, too! But, setting up and using is not so difficult at all, really. To get the artistic side you want..that is the challenge. Best wishes on whatever your choice in external lighting. Post please if and when it happens since I have a lot to learn here. Thanks. Tom.