The FlexTT5 is a dedicated Nikon E-TTL II radio transceiver. Key features include:
“Pass-through” hot-shoe mount
Triggers flashes and cameras
Triggers all PocketWizard units
Remote Multi-Unit Triggering. The FlexTT5 can trigger slave PocketWizards up to 800 feet away, even outside of the line of sight. It supports multiple slave units, which are triggered by additional FlexTT5 units set as receivers, or by standard PocketWizards (without TTL data passed through, in this case). You can use the camera, an on-camera flash, or flash-commander controls to control the flash for up to 20 TTL units.
“Pass-Through” Hot-Shoe Mount. This unit slides onto the camera’s hot shoe. It sits flat on top of the camera with only a small flip-up antenna for when you need maximum range, and has a “pass-through” hot-shoe mount on top, giving you the option of using an on-camera shoe-mounted flash in addition to off-camera flashes.