A YN585EX supports receiving wireless signal from the master unit of AF-350FGZ, AF-540FGZ II and other Pentax cameras. It also supports 4 channels, off-camera TTL and manual flash. YN585EX supports FEC, FEB, Rear-curtain sync and red eye reduction. It features GN58@ ISO100, 105mm; supports TTL, M and Multi mode. YN585EX can be triggered through the camera, wireless triggered by the built-in flash or master flash, or triggered in S1/S2 pre-flash avoidance mode. YN585EX is equipped with USB port. It¡¯s convenient to visit the official website of YONGNUO, download the latest firmware and upgrade the speedlite. Supports auto and manual zooming, the flash can coverage can be changed between 20~ 105mm. The Charging recycle time is 3s when the speedlite is used with maximum output power. The charging recycle time is about 4~5s even the speedlite is not used with brand new batteries. YN585EX is equipped with AF Assist Beam. Quick focus is easily to be realized in dark environment. Advanced Options Settings and Auto Save settings. Equipped with Big Size LCD Display Screen, Standard PC synchronous Interface