The -SF3000 Slave Flash can be used for both direct hot shoe photography (when switched to ""Normal Mode"") and remote flash photography (when switched to ""Slave On""). This flash also features four slave modes that allow it to work with cameras that fire their built in flash instantaneously or cameras that have a single or multiple flash red eye reduction system. Uses 2 AA Batteries Auto Pre-Flash Sensor Built-in Digital Slave Includes Camera hot Shoe Bracket Ultra-Light Weight Compact Design For Use with Digital SLR Cameras