PLR Studio Series Pro Slave Flash Includes Mounting Bracket For The Sony Alpha DSLR SLT-A33, A35, A37, A55, A57, A65, A77, A77 II, A99, A100, A200, A230, A290, A300, A330, A350, A380, A390, A450, A500, A560, A550, A700, A850, A900 & Minolta Maxxum Digital SLR Cameras Automatically synchronizes with your cameras internal or external flash - without wires or remote triggering devices Compact design makes it ideal for placing behind subject to eliminate shadows, create dramatic effects, etc Variable power settings let you control light output Pre flash sensor eliminates accidental triggering by red eye reduction mode Standard shoe mount and external bracker for multiple camera mounting options