Pixel X800C Speedlite Faster Back Power for Canon Digital SLR Cameras SUPPORT PIXEL KING PRO WIRELESS TRIGGERING: It can controlling by KING PRO transmitter directly without attaching the receiver. MASTER/SLAVE: The X800C PRO flash not only support FSK 2.4GHz wireless control, but also support optical wireless Master/Slave and S1/S2 control. FAST RECYCLING TIME: The X800C PRO flash recycling time is less than 2.5 sec on 1/1 full power output. It enables you to capture more wonderful moments easily. RROBOSCOPIC FLASH MODE: It's compatible with a variety of flash modes, such as ETTL/M/RPT. It is compatible with all Canon DSLR cameras. The stroboscopic flash duration is up to 500Hz. ENERGY-SAVING DESIGN: Ultra-high energy-saving design. Due to the advances is boots voltage and stand-by scheme, the battery life is extended and allows 180 exposures on full power. The stand-by time is ultra-long which greatly lowered the battery power consumption compared to other similar products.