The dedicated flasher unit (DFL) is part of the light module of a kit that allows you to integrate 2 Railroad Crossings together with 2 side-on Detectors and 1 crossing bell or block detectors, all controlled by the Lamplighter DFL unit.
It comes in two versions, one with a power supply and the other without.
There is absolutely no programming nor soldering required. The 3 wires from the detectors and crossing bell need to be attached to the DFL unit using screws built into it. It couldn't be easier.