Yongnuo YN560 II Speedlite Slave Multi Manual Flash for Canon EOS Nikon DSLR Pentax Olympus Panasnic Digital Camera Slave function ( S1, S2 mode): You just can use YN-460 and YN-460 II in indoor and at a very weak light, but for YN-560, you can use it in outdoor environment, and the wireless triggering distance is as around 15m The High Sensitivity Wireless Triggering Sensor: The high sensitivity wireless triggering sensor inherits from YN560, which makes the S1 and S2 mode can be used in outdoor environment and the wireless triggering distance is as long as 15m, as well as 25m indoors. Large LCD Panel: Large LCD panel, you can look into and set the functions on the LCD panel clearly and directly. New Power zoom function: You can push the button on the flash and make it covered focal length range from 24mm to 105mm Batteries and Camera is not include