Control Unit, Train 4.5V Whistle Brick 4 x 8 x 2 with Forward/Stop/Reverse Functions

Control Unit, Train 4.5V Whistle Brick 4 x 8 x 2 with Forward/Stop/Reverse Functions (part upn0313b) is a Electronics used in 2 official LEGO sets. Scan or search to authenticate loose parts and check market value. Open the parent-set list to see which themes and years used this mold — essential when a common shape appears in a rare color or print.