The MiniTT1 transmitter is a low-profile unit that slides directly into the camera"s hot shoe. It takes the complex TTL flash data sent through the camera"s hot shoe contacts and transmits it in a secure, unique PocketWizard radio signal. Flash units must be mounted on a FlexTT5 transceiver for TTL operation or any PocketWizard unit for manual operation. Shoot FP sync up to 1/8000 sec. with Nikon Speedlites or up to 1/500 sec. and faster with full-power manual flash units using exclusive PocketWizard HyperSync. The unique ControlTL system enables adjustable Pre-Flash Boost for better autoflash shooting and remote autoflash at up to 7 fps. As all communication takes place through the dedicated hot shoes, there is no need for cables, brackets, Velcro or tape to use them. The FlexTT5 transceiver shares the MiniTT1 transmitter"s features and adds the advanced auto-sensing and relay modes introduced with the PocketWizard Plus II, as well as camera and flash ports for PocketWizard cable connection to any camera or flash system. Both units feature a two-position channel selector that is factory programmed to the PocketWizard classic channel one and two. Using PocketWizard Utility software, available free on www.PocketWizard.com, and the USB port, you can program either channel to any of the PocketWizard system"s 32 Standard or 20 ControlTL digitally encoded channels and zones. A special Learning Mode enables simple, in-the-field programming of all channels. The MiniTT1 transmitter and FlexTT5 transceiver represent a new era of PocketWizard software technology. Simply connect one of the units to a computer and click a button and it automatically updates its firmware. This allows for virtually unlimited system upgrades for new functionality and makes these PocketWizard radios capable of meeting any future challenge.