Product The signal has a gray mast with a movable arm and movable disk. The signal changes from (Vr 0) to green/green (Vr 1) or to yellow/green (Vr 2). It has 2 servos. Publications - New items brochure 2018 Features Digital decoder with additional, digitally controlled functions (f1, f2, f3 or f4) when operated with the 6021 Control Unit. The functions present depend on how the locomotive is equipped. Standard function (function) active during conventional operation. Digital decoder with up to 32 digitally controlled functions. The quantity depends on the controller being used. DCC decoder Era 3 Era 4 Digital decoder with additional, digitally controlled functions (f1, f2, f3 or f4) when operated with the 6021 Control Unit. The functions present depend on how the locomotive is equipped. Standard function (function) active during conventional operation. Digital decoder with up to 32 digitally controlled functions. The quantity depends on the controller being used. DCC decoder Era 3 Era 4