PocketWizard Canon AC9 AlienBees Adapter (Black) Only products shipped from and sold by authorized resellers such as Amazon.com can ensure that you are receiving product that has proper FCC communication and is covered by the US Warranty. Control flash power level with cameras Flash Exposure Control (FEC). PowerTracking automatically adjusts flash power to maintain levels Powered by FlexTT5; no need to install or replace batteries Use with PocketWizard AC3 ZoneController for control of three flashes in 1/3- stop increments over a six-stop range.