"The key to wireless triggering and TTL remote control is Profoto's Air Remote TTL-C transmitter, available for Canon cameras. Operating on 2.4GHz bandwidth, the transmitter, really a controller, has 8 frequency channels and with 3 groups per channel and a range of up to 330' for TTL triggering and 1,000' for normal triggering. Each channel has power ratio capability of +/- 2 stops. If you prefer to use manual you have +/- 9 stops power variation. You've also got modeling light, unit shut-down and first or rear curtain control. Both the TTL-C and the B1 500 Air TTL have mini-USB connectors for firmware updates directly from Profoto's website. The Air Remote TTL-C will also trigger non-TTL Air heads and packs from Canon cameras but without the TTL feature.|Off-Camera TTL Control for Profoto AirTTL Flashes: Place the Air Remote TTL-C on your camera hot shoe to merge your camera's TTL with your Profoto AirTTL flash. Then point-and-shoot and let the camera/flash technology automatically adjust the light o|Remote Control for Profoto Air Flashes: With the Air Remote TTL-C you can remote control multiple Profoto Air flashes directly from your camera. You can control an endless number of lights in up to 3 groups from up to 330' in TTL and 1,000 ft in manu|Fast and Reliable Flash Sync: Air is one of the most reliable wireless systems available to sync your flashes with your camera. It is also fast enough to provide flash sync with to the fastest X-sync speed of your camera. If you are using Profoto Air|A Wireless System with a Wide Range of Options: Air Remote TTL-C is an integrated part of a wide range of Air products comprised of camera transceivers, accessory cables and software, all designed to offer a better wireless solution for professional"