Yongnuo YN560 speedlite IV wireless flash for canon and Nikon has 2.4 GHz transceiver with 328' range, guide number 190' at ISO 100 and 105mm, zoom range 24-105mm, output range 1/1 to 1/128, tilts-7 to 90° and rotates 270°, optical slave functionality, three seconds recycle time, multi-mode for firing series of flashes, PC sync and HV power ports, runs on four AA batteries.