This is the Bandai 5056759 LED Unit (Blue)

This blue LED unit can be used for various Gundam kits and the 1/1000 Space Battleship Yamato model kit series! Two LR41 button-cell batteries are required, and are sold separately; instructions for installation are written on the back of the box.

• Blue LED unit that can be used for various items!
• Can be used for 1/1000 Space Battleship Yamato series and various Gundams
• Button battery LR41 × 2 pieces (sold separately) is required
• One LED light included