The Flashpoint Zoom Li-on R2 TTL Flash for Canon represents a significant breakthrough in speedlight power technology with the introduction of full R2 Remote TTL connectivity and interaction with all Canon strobe functions. From standard ETTL, to Exposure Compensation (FEC), FV Lock, High Speed Sync, and an automatically zooming flashhead, all the way to complete ETTL II control connectivity with other Canon flashes, group control, Slave and Master options, and advanced flash functions, the Zoom Li-on flash takes you as far as you want to go. The R2 TTL Wireless Flash System is the advanced 2.4GHz radio remote that adds camera TTL dedicated custom functions to your multi flash experience. Easy to use buttons command a full range of functions like reliable channel triggering, group mode selectivity, HSS, with powerful signal strength and exceptional stability to your selected camera flash language. The LCD panel clearly display the status of all remote R2 compliant strobes so you always have control of group lighting setup. R2 wireless communication gives speed of light response to on camera or off camera R2 family devices for a spectacular advantage on the shoot in any environment. The other massive advantage is the internal and interchangeable Lithium Ion Polymer battery with exponentially more power than AA batteries of any type, while fitting into roughly the same amount of space. Packing an amazing 11.1 volts and 2000mAh, this battery