This kit includes 2 FlexTT5 Transceivers for Canon, an AC3 ZoneController, and a G-Wiz Trunk. it is a perfect starter kit for one off camera flash or add a FlexTT6 as a transmitter and you can control 2 remote Canon Speedlite units in either manual or TTL.
The FlexTT5 is TTL compatible with older Canon cameras, up to approximately early 2016. Newer generation cameras, starting with the 5D Mark IV and 1DX Mark II, require the FlexTT6 to be used as the transmitting radio for TTL communication. The FlexTT5s can be also used with current cameras in Basic Trigger mode for manual shooting, up to X-sync. Please see our Wiki page for details about compatibility.