PocketWizard AC3 Zone Controller for Canon cameras
The Pocket Wizard AC3 ZoneController allows you to control your flash set up directly from your camera's position. Simply add it to your on-camera Mini TT1 Transmitter or Flex TT5 Transceiver and you instantly have three zones of flash control whether working in E-TTL II or Manual model. Put your flashes wherever you want without worrying about having to access them during a shoot. With the AC3 ZoneController, you are in total control of your flash. Three clearly labeled dials allow you to increase or decrease power to three zones of flash in 1/3-stop increments with a range of up to six stops. Three switches allow you to change zones between Manual, Auto (PowerTracking/E-TTL II) or OFF. Best of all, the design is simple with an intuitive interface.