In addition to working with the Nikon autofocus cameras, the Metz SCA 3402 adapter also brings wireless TTL auxiliary flash capacity to other makes of cameras when combined with Nikons 3073 SU-4 wireless slave flash controller. For example, if you had a camera with TTL flash capacity but did not have a cord to connect the system to an auxiliary flash and wished to have TTL with a second off-camera flash unit, youd be out of luck.