The AC3 ZoneController is the gem of the ControlTL product line. Add it to your on-camera MiniTT1 Transmitter or FlexTT5 Transceiver and you instantly have three zones of flash control. Whether working in TTL or Manual mode, you can control your remote flashes directly from the camera position. Available for both Nikon and Canon. Photographers can now take their AC3 and transmitting radio off-camera and use it to set power levels for any flash with a ControlTL receiver, making it more convenient to use an optically triggered light meter, or control the power levels with just a MiniTT1/FlexTT5 and AC3 in their hand while another photographer takes the pictures. Previously, an AC3 ZoneController on a MiniTT1 or FlexTT5 needed to be on camera to send manual power levels to remote flashes. Now, when connected to a MiniTT1 or FlexTT5, manual power levels are transmitted to remote flashes when the TEST button is pressed even when the transmitter is off the camera. This affects both speedlights connected to receiving FlexTT5s and larger flashes like AlienBees and Elinchrom RX units with ControlTL receivers.