The Pocket Wizard Flash Confirmation Cable indicates that a flash connected to your MultiMax Transceiver actually fired. By utilizing a shielded high intensity light sensor, which only remains active during the brief radio transmitting time, it confirms only if the attached flash fired or not. Flash confirmation status is sent to the attached receiver and in return sent back to the transmitter. A visual confirmation icon appears on the LCD screen confirming whether the flash fired on all four Quad-Triggering zones.