OC E3 —— It is a special remoted cable for Canon EOS series, it control the flash simultaneously by connecting Canon camera and the external flashgun, the function as well which set on the top of the camera. Support all functions of Canon EOS, as well all E-TTL functions of Canon flash system.

SC 28 ——This TTL Remote Cord provides full TTL control for Nikon Speedlites when used off-camera with Nikon SLR cameras which have the TTL hot flash shoe. 2.5' long & coiled, it permits easy use of flash when the camera is mounted upon a bracket.

FC-681 —— This FC-681 is a good accessory used to achieve off-camera flash photography works without the harsh shadows behind the subjects, or achieve special lighting for the subject. This item is an upgrade version of Yongnuo OC-E3 TTL cord, it has a hot shoe at each end, so you can use it for two flashes at the same time.

FC-682 —— This FC-682 is a good accessory used to achieve off-camera flash photography works without the harsh shadows behind the subjects, or achieve special lighting for the subject.This item is an upgrade version of Yongnuo SC-28 TTL cord, it has a hot shoe at each end, so you can use it for two flashes at the same time