The pocketwizard ttl 4 pack is the ideal solution to compliment your existing flextt5 or minitt1 to expand your lighting controlconsisting of 2 x flextt5 transceivers an ac3 zonecontroller and a g wiz uber bag the flextt5 transceivers can be attached to off camera flashes or lights to allow them to be controlled by the minitt1 transmitter or additional flextt5 add the ac3 zonecontroller to the on camera flextt5minitt1 transceiver to create up to three zones of flash control in both ttl