i think your talking about this
http://www.bhphotovideo.com/c/product/441353-REG/PocketWizard_801_125_Plus_II_Transceiver_Radio.html
The
PocketWizard Plus II Transceiver/Relay is a triggering system that offers Auto-Sensing Transceiver Technology. This technology analyzes the status of the Plus II's miniphone jacks, camera hot shoe or the TEST button to determine which mode (Transmit or Receive) to set itself. By default, the Plus II is always in Receiver mode unless it senses a trigger pulse from a camera's hot shoe. It then quickly switches to Transmitter mode. The Auto-Sensing feature can also be disabled, if necessary.
This unit can also be used as a relay. You can remotely trigger your camera, and the camera-mounted transceiver automatically relays the triggering signal to a remote flash. With the Plus II's fast switching speed, there's no loss of camera shutter speed performance or triggering delays.
Note! This is one unit only. A minimum of two units are required.
Key Features
Backward Compatible with All Previous Pocket Wizards Compatible with PocketWizard Plus, the first 4 channels of Original Pocket Wizard, and MultiMax; it is also part of the PocketWizard Wireless Freedom system. Triggers a Camera or Flash The powerful microprocessor will automatically trigger a camera and remote flash within 10 microseconds (1/100th of a millisecond) with its built-in Auto-Relay mode. Keeps Up with Your Camera's Top Firing Speed The Plus II sports the fastest triggering speed in its class, at an amazing 12 fps; it can out pace the fastest D-SLR's available. Keeps Up with Your Camera's Top Sync Speed The Pocket Wizard II will work with sync speeds of up to 1/250 second on focal plane shutter cameras, and 1/500 second on leaf shutter cameras. Channel or Zone Firing Four selectable channels provide secure triggering. Choosing which zone to trigger (on camera flash, remote flash or both) is as easy as sliding a switch.