Brand new 4 channel wireless flash trigger PT-04TM. Channel: 4 control channels. Control rage: up to 50 meters (open area without interference). Shutter sync speed: up to 1/1000 second. Receiver battery: two AAA batteries (Batteries not included). More stable, no misfiring tested and should be compatible with most of the flash guns such as Canon 580/430EX, Nikon SB600/800. This wireless trigger is control discreteness for camera to trigger hot shoe flashgun synchronously. The signal transmitter makes of advanced circuit design and comport. It can transmit wireless signal that is being encoded with low power consumption. Reciever is power supplied by two AAA batteries.