The Yongnuo YNE3-RX ETTL is compatible with Canon's RT flash system, allowing E-TTL flashes compatibility with RT master flashes including the Canon 600EX-RT, Yongnuo YN600EX-RT. The YNE3-RX is also compatible with the ST-E3-RT & YN-E3-RT commanders. 

The receiver has a 1/4"-20 female mounting thread, a female hot shoe, and USB port for firmware upgrades. Operating on the 2.4 GHz frequency, the receiver has 15 channels to thwart interference and can wirelessly trigger flash units in any of its 5 groups singly or in unison at distances up to 328'. The user-friendly LCD screen allows monitoring of channel and groups in use, battery level and /- flash exposure compensation. It also indicates E-TTL, Manual or Multi (stroboscopic) flash mode selection.