Aputure Magmum MG-68 Flash Speedlite for Nikon, Canon, Olympus, Pentax, Panasonic Cameras 4 Seconds to Recycle to Full Brightness, Precise Brightness Adjustment 3 Flash Modes(M/S1/S2) Optical Sensor, Power Saving Mode, External Power Port PC Sync Port, Overheating Protection 24 Month Manufacture Warranty