Internal TTL circuitry and hot shoe for use with certain Ikelite housings for Sony cameras, see housing compatibility below. Easy installation into the housing with a secure fit underneath the camera mounting tray.
Through-The-Lens (TTL) metering takes advantage of the Sony camera's ability to measure the light through the lens and automatically adjust strobe power.
Housing compatibility as of December 2017:
DL200 Housing for Sony A7 II, A7R II, A7R III
DL200 Housing for Sony A9
Not compatible with any other models except as listed above.