4L-001-006 GWR Junction LH 2 Arms LH Short Post SignalFinely detailed semaphore signal. This signal comes ready made with working arm and led lighting in the appropriate colours to match signal. The arm raises and lowers slowly to add to the realism. To power this signal you will need a smooth 12v DC supply. We recommend our GMC WM4 plug in transformer. Included in the pack is the Servo control box which the signal plugs into. This box powers and controls the raising and lowering of the signal arms and