Thank you for viewing. [Defective] LEGO controller and LEGO battery. My child saved up their allowance and purchased this controller, but it either used infrared or the main unit wasn't working well, and it only responded at close range. Therefore, they bought a new infrared LED separately online and, using a soldering iron, the child installed the new infrared LED themselves. Even after installing the infrared LED, the response was the same, only working at close range, and then it stopped working after a while, so I decided to list it for sale. I have taken photos of the installed infrared LED after opening it up. Please check them. How about for disassembly or parts? *The LEGO battery works. It works, but one of the springs in the battery compartment has rust. The following is a text my child wrote: ↓ "First, the LEGO controller's infrared doesn't work. There are traces of the infrared LED being repaired, so you are responsible if it breaks or something dangerous happens. Therefore, please consider the LEGO controller as junk. The LEGO battery works properly and functions, but as you can see in the photo, there is a little rust, so you are also responsible for this." Due to the above reasons, please purchase only if you understand that these are used items. Please refrain from purchasing if you are concerned about details. Due to Mercari's listing specifications, some parts are censored.