The Canon Speedlite 600EX II-RT is a professional-grade flash delivering powerful, reliable wireless flash photography. Featuring a guide number of 197 feet at ISO 100 and 200mm with an impressive zoom range from 20-200mm (extending to 14mm with the wide panel), this top-of-the-line Speedlite offers advanced lighting control for weddings, events, and fast-paced shooting. Built-in 2.4 GHz radio transmission provides wireless operation at ranges up to 98.4 feet across up to 15 individual flashes organised in 5 groups, whilst dual optical and radio transmission modes deliver flexibility. Improved continuous flash performance is 1.1-1.5 times faster than previous models (up to 2.0x with optional battery pack), with a weather-sealed, dust and water-resistant body engineered for professional durability. The intuitive backlit LCD display, customisable controls, and included bounce adapter and colour filters make this flash ideal for comprehensive lighting setups on location or in studio. Powered by four AA batteries.