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Electric, Train 4.5V Whistle Control Block 4 x 8 x 2 with Forward/Stop/Reverse Functions
Bricklink ID:x871b
Weight:28.000 g
x871b

Sets with this part (from Bricklink)
  Part color Trans-Clear
 


 Set nameRelease yearQuantity
139139 Electronic Control Unit (F/B-Stop)19691
138138 Electronic Train, F/B-Stop19681