This Sekonic L-358 Flash Master features flash/ambient analyzing in all flash modes, and an optional RT-32N plug-in internal radio transmitter module that eliminates the need for cord connections while measuring flash up to 100 feet away (when flash units are used with pocket wizards). With options such as shutter speeds and apertures selectable in 1, 1/2 or 1/3 stop increments the L-358 makes operation most efficient by matching the displayed f/stop and shutter speed values to the photographer's camera.