Cruise Flaps, the function is called the Trailing Edge Variable Camber (TEVC) function. It actually has two functions, but the drag reduction function uses the inboard trailing edge to reduce drag during the cruise. It works above 25,000ft and an actuator between the inboard and outboard flaps disconnects and holds the outboard flaps in place. This then allows the inboard flaps to move using the electric motor on the flap power control unit. Can't remember the exact authority of the system but it is only a few degrees and moves in increments of 0.5 degrees if I recall right.