High quality Flash Wave III TX radio transmitter can be mounted directly to the standard hot shoe of your camera or connected to a sync socket (cable included). 2.4GHz signal and 16 selectable channels encrypted to trigger external flash devices with Flash Wave RX-III radio receiver. Maximum transmission distance is 700 feet. TX Dimensions: 1-1/4" x 3" x 1" Package Includes: 1 x Flash Wave III TX Transmitter, 1 x PC Sync Cable, 1 x CR2450 Lithium Battery